×  Vincent Selhorst-Jones

Intro to Polynomials

Slide Duration:

Section 1: Introduction
Introduction to Precalculus

10m 3s

Intro
0:00
Title of the Course
0:06
Different Names for the Course
0:07
Precalculus
0:12
Math Analysis
0:14
Trigonometry
0:16
Algebra III
0:20
Geometry II
0:24
College Algebra
0:30
Same Concepts
0:36
How do the Lessons Work?
0:54
Introducing Concepts
0:56
Apply Concepts
1:04
Go through Examples
1:25
Who is this Course For?
1:38
Those Who Need eExtra Help with Class Work
1:52
Those Working on Material but not in Formal Class at School
1:54
Those Who Want a Refresher
2:00
Try to Watch the Whole Lesson
2:20
Understanding is So Important
3:56
What to Watch First
5:26
Lesson #2: Sets, Elements, and Numbers
5:30
Lesson #7: Idea of a Function
5:33
Lesson #6: Word Problems
6:04
What to Watch First, cont.
6:46
Lesson #2: Sets, Elements and Numbers
6:56
Lesson #3: Variables, Equations, and Algebra
6:58
Lesson #4: Coordinate Systems
7:00
Lesson #5: Midpoint, Distance, the Pythagorean Theorem and Slope
7:02
Lesson #6: Word Problems
7:10
Lesson #7: Idea of a Function
7:12
Lesson #8: Graphs
7:14
Graphing Calculator Appendix
7:40
What to Watch Last
8:46
Let's get Started!
9:48
Sets, Elements, & Numbers

45m 11s

Intro
0:00
Introduction
0:05
Sets and Elements
1:19
Set
1:20
Element
1:23
Name a Set
2:20
Order The Elements Appear In Has No Effect on the Set
2:55
Describing/ Defining Sets
3:28
Directly Say All the Elements
3:36
Clearly Describing All the Members of the Set
3:55
Describing the Quality (or Qualities) Each member Of the Set Has In Common
4:32
Symbols: 'Element of' and 'Subset of'
6:01
Symbol is ∈
6:03
Subset Symbol is ⊂
6:35
Empty Set
8:07
Symbol is ∅
8:20
Since It's Empty, It is a Subset of All Sets
8:44
Union and Intersection
9:54
Union Symbol is ∪
10:08
Intersection Symbol is ∩
10:18
Sets Can Be Weird Stuff
12:26
Can Have Elements in a Set
12:50
We Can Have Infinite Sets
13:09
Example
13:22
Consider a Set Where We Take a Word and Then Repeat It An Ever Increasing Number of Times
14:08
This Set Has Infinitely Many Distinct Elements
14:40
Numbers as Sets
16:03
Natural Numbers ℕ
16:16
Including 0 and the Negatives ℤ
18:13
Rational Numbers ℚ
19:27
Can Express Rational Numbers with Decimal Expansions
22:05
Irrational Numbers
23:37
Real Numbers ℝ: Put the Rational and Irrational Numbers Together
25:15
Interval Notation and the Real Numbers
26:45
Include the End Numbers
27:06
Exclude the End Numbers
27:33
Example
28:28
Interval Notation: Infinity
29:09
Use -∞ or ∞ to Show an Interval Going on Forever in One Direction or the Other
29:14
Always Use Parentheses
29:50
Examples
30:27
Example 1
31:23
Example 2
35:26
Example 3
38:02
Example 4
42:21
Variables, Equations, & Algebra

35m 31s

Intro
0:00
What is a Variable?
0:05
A Variable is a Placeholder for a Number
0:11
Affects the Output of a Function or a Dependent Variable
0:24
Naming Variables
1:51
Useful to Use Symbols
2:21
What is a Constant?
4:14
A Constant is a Fixed, Unchanging Number
4:28
We Might Refer to a Symbol Representing a Number as a Constant
4:51
What is a Coefficient?
5:33
A Coefficient is a Multiplicative Factor on a Variable
5:37
Not All Coefficients are Constants
5:51
Expressions and Equations
6:42
An Expression is a String of Mathematical Symbols That Make Sense Used Together
7:05
An Equation is a Statement That Two Expression Have the Same Value
8:20
The Idea of Algebra
8:51
Equality
8:59
If Two Things Are the Same *Equal), Then We Can Do the Exact Same Operation to Both and the Results Will Be the Same
9:41
Always Do The Exact Same Thing to Both Sides
12:22
Solving Equations
13:23
When You Are Asked to Solve an Equation, You Are Being Asked to Solve for Something
13:33
Look For What Values Makes the Equation True
13:38
Isolate the Variable by Doing Algebra
14:37
Order of Operations
16:02
Why Certain Operations are Grouped
17:01
When You Don't Have to Worry About Order
17:39
Distributive Property
18:15
It Allows Multiplication to Act Over Addition in Parentheses
18:23
We Can Use the Distributive Property in Reverse to Combine Like Terms
19:05
Substitution
20:03
Use Information From One Equation in Another Equation
20:07
20:44
Example 1
23:17
Example 2
25:49
Example 3
28:11
Example 4
30:02
Coordinate Systems

35m 2s

Intro
0:00
Inherent Order in ℝ
0:05
Real Numbers Come with an Inherent Order
0:11
Positive Numbers
0:21
Negative Numbers
0:58
'Less Than' and 'Greater Than'
2:04
2:56
Inequality
4:06
Less Than or Equal and Greater Than or Equal
4:51
One Dimension: The Number Line
5:36
Graphically Represent ℝ on a Number Line
5:43
Note on Infinities
5:57
With the Number Line, We Can Directly See the Order We Put on ℝ
6:35
Ordered Pairs
7:22
Example
7:34
Allows Us to Talk About Two Numbers at the Same Time
9:41
Ordered Pairs of Real Numbers Cannot be Put Into an Order Like we Did with ℝ
10:41
Two Dimensions: The Plane
13:13
We Can Represent Ordered Pairs with the Plane
13:24
Intersection is known as the Origin
14:31
Plotting the Point
14:32
Plane = Coordinate Plane = Cartesian Plane = ℝ²
17:46
18:50
19:04
19:21
20:04
20:20
Three Dimensions: Space
21:02
Create Ordered Triplets
21:09
Visually Represent This
21:19
Three-Dimension = Space = ℝ³
21:47
Higher Dimensions
22:24
If We Have n Dimensions, We Call It n-Dimensional Space or ℝ to the nth Power
22:31
We Can Represent Places In This n-Dimensional Space As Ordered Groupings of n Numbers
22:41
Hard to Visualize Higher Dimensional Spaces
23:18
Example 1
25:07
Example 2
26:10
Example 3
28:58
Example 4
31:05
Midpoints, Distance, the Pythagorean Theorem, & Slope

48m 43s

Intro
0:00
Introduction
0:07
Midpoint: One Dimension
2:09
Example of Something More Complex
2:31
Use the Idea of a Middle
3:28
Find the Midpoint of Arbitrary Values a and b
4:17
How They're Equivalent
5:05
Official Midpoint Formula
5:46
Midpoint: Two Dimensions
6:19
The Midpoint Must Occur at the Horizontal Middle and the Vertical Middle
6:38
Arbitrary Pair of Points Example
7:25
Distance: One Dimension
9:26
Absolute Value
10:54
Idea of Forcing Positive
11:06
Distance: One Dimension, Formula
11:47
Distance Between Arbitrary a and b
11:48
Absolute Value Helps When the Distance is Negative
12:41
Distance Formula
12:58
The Pythagorean Theorem
13:24
a²+b²=c²
13:50
Distance: Two Dimensions
14:59
Break Into Horizontal and Vertical Parts and then Use the Pythagorean Theorem
15:16
Distance Between Arbitrary Points (x₁,y₁) and (x₂,y₂)
16:21
Slope
19:30
Slope is the Rate of Change
19:41
m = rise over run
21:27
Slope Between Arbitrary Points (x₁,y₁) and (x₂,y₂)
22:31
Interpreting Slope
24:12
Positive Slope and Negative Slope
25:40
m=1, m=0, m=-1
26:48
Example 1
28:25
Example 2
31:42
Example 3
36:40
Example 4
42:48
Word Problems

56m 31s

Intro
0:00
Introduction
0:05
What is a Word Problem?
0:45
Describes Any Problem That Primarily Gets Its Ideas Across With Words Instead of Math Symbols
0:48
Requires Us to Think
1:32
Why Are They So Hard?
2:11
Reason 1: No Simple Formula to Solve Them
2:16
Reason 2: Harder to Teach Word Problems
2:47
You Can Learn How to Do Them!
3:51
7:57
'But I'm Never Going to Use This In Real Life'
9:46
Solving Word Problems
12:58
First: Understand the Problem
13:37
Second: What Are You Looking For?
14:33
Third: Set Up Relationships
16:21
Fourth: Solve It!
17:48
Summary of Method
19:04
Examples on Things Other Than Math
20:21
Math-Specific Method: What You Need Now
25:30
Understand What the Problem is Talking About
25:37
Set Up and Name Any Variables You Need to Know
25:56
Set Up Equations Connecting Those Variables to the Information in the Problem Statement
26:02
Use the Equations to Solve for an Answer
26:14
Tip
26:58
Draw Pictures
27:22
Breaking Into Pieces
28:28
Try Out Hypothetical Numbers
29:52
Student Logic
31:27
Jump In!
32:40
Example 1
34:03
Example 2
39:15
Example 3
44:22
Example 4
50:24
Section 2: Functions
Idea of a Function

39m 54s

Intro
0:00
Introduction
0:04
What is a Function?
1:06
A Visual Example and Non-Example
1:30
Function Notation
3:47
f(x)
4:05
Express What Sets the Function Acts On
5:45
Metaphors for a Function
6:17
Transformation
6:28
Map
7:17
Machine
8:56
Same Input Always Gives Same Output
10:01
If We Put the Same Input Into a Function, It Will Always Produce the Same Output
10:11
Example of Something That is Not a Function
11:10
A Non-Numerical Example
12:10
The Functions We Will Use
15:05
Unless Told Otherwise, We Will Assume Every Function Takes in Real Numbers and Outputs Real Numbers
15:11
Usually Told the Rule of a Given Function
15:27
How To Use a Function
16:18
Apply the Rule to Whatever Our Input Value Is
16:28
Make Sure to Wrap Your Substitutions in Parentheses
17:09
Functions and Tables
17:36
Table of Values, Sometimes Called a T-Table
17:46
Example
17:56
Domain: What Goes In
18:55
The Domain is the Set of all Inputs That the Function Can Accept
18:56
Example
19:40
Range: What Comes Out
21:27
The Range is the Set of All Possible Outputs a Function Can Assign
21:34
Example
21:49
Another Example Would Be Our Initial Function From Earlier in This Lesson
22:29
Example 1
23:45
Example 2
25:22
Example 3
27:27
Example 4
29:23
Example 5
33:33
Graphs

58m 26s

Intro
0:00
Introduction
0:04
How to Interpret Graphs
1:17
Input / Independent Variable
1:47
Output / Dependent Variable
2:00
Graph as Input ⇒ Output
2:23
One Way to Think of a Graph: See What Happened to Various Inputs
2:25
Example
2:47
Graph as Location of Solution
4:20
A Way to See Solutions
4:36
Example
5:20
Which Way Should We Interpret?
7:13
Easiest to Think In Terms of How Inputs Are Mapped to Outputs
7:20
Sometimes It's Easier to Think In Terms of Solutions
8:39
Pay Attention to Axes
9:50
Axes Tell Where the Graph Is and What Scale It Has
10:09
Often, The Axes Will Be Square
10:14
Example
12:06
Arrows or No Arrows?
16:07
Will Not Use Arrows at the End of Our Graphs
17:13
Graph Stops Because It Hits the Edge of the Graphing Axes, Not Because the Function Stops
17:18
How to Graph
19:47
Plot Points
20:07
Connect with Curves
21:09
If You Connect with Straight Lines
21:44
Graphs of Functions are Smooth
22:21
More Points ⇒ More Accurate
23:38
Vertical Line Test
27:44
If a Vertical Line Could Intersect More Than One Point On a Graph, It Can Not Be the Graph of a Function
28:41
Every Point on a Graph Tells Us Where the x-Value Below is Mapped
30:07
Domain in Graphs
31:37
The Domain is the Set of All Inputs That a Function Can Accept
31:44
Be Aware That Our Function Probably Continues Past the Edge of Our 'Viewing Window'
33:19
Range in Graphs
33:53
Graphing Calculators: Check the Appendix!
36:55
Example 1
38:37
Example 2
45:19
Example 3
50:41
Example 4
53:28
Example 5
55:50
Properties of Functions

48m 49s

Intro
0:00
Introduction
0:05
Increasing Decreasing Constant
0:43
Looking at a Specific Graph
1:15
Increasing Interval
2:39
Constant Function
4:15
Decreasing Interval
5:10
Find Intervals by Looking at the Graph
5:32
Intervals Show x-values; Write in Parentheses
6:39
Maximum and Minimums
8:48
Relative (Local) Max/Min
10:20
Formal Definition of Relative Maximum
12:44
Formal Definition of Relative Minimum
13:05
Max/Min, More Terms
14:18
Definition of Extrema
15:01
Average Rate of Change
16:11
Drawing a Line for the Average Rate
16:48
Using the Slope of the Secant Line
17:36
Slope in Function Notation
18:45
Zeros/Roots/x-intercepts
19:45
What Zeros in a Function Mean
20:25
Even Functions
22:30
Odd Functions
24:36
Even/Odd Functions and Graphs
26:28
Example of an Even Function
27:12
Example of an Odd Function
28:03
Example 1
29:35
Example 2
33:07
Example 3
40:32
Example 4
42:34
Function Petting Zoo

29m 20s

Intro
0:00
Introduction
0:04
Don't Forget that Axes Matter!
1:44
The Constant Function
2:40
The Identity Function
3:44
The Square Function
4:40
The Cube Function
5:44
The Square Root Function
6:51
The Reciprocal Function
8:11
The Absolute Value Function
10:19
The Trigonometric Functions
11:56
f(x)=sin(x)
12:12
f(x)=cos(x)
12:24
Alternate Axes
12:40
The Exponential and Logarithmic Functions
13:35
Exponential Functions
13:44
Logarithmic Functions
14:24
Alternating Axes
15:17
Transformations and Compositions
16:08
Example 1
17:52
Example 2
18:33
Example 3
20:24
Example 4
26:07
Transformation of Functions

48m 35s

Intro
0:00
Introduction
0:04
Vertical Shift
1:12
Graphical Example
1:21
A Further Explanation
2:16
Vertical Stretch/Shrink
3:34
Graph Shrinks
3:46
Graph Stretches
3:51
A Further Explanation
5:07
Horizontal Shift
6:49
Moving the Graph to the Right
7:28
Moving the Graph to the Left
8:12
A Further Explanation
8:19
Understanding Movement on the x-axis
8:38
Horizontal Stretch/Shrink
12:59
Shrinking the Graph
13:40
Stretching the Graph
13:48
A Further Explanation
13:55
Understanding Stretches from the x-axis
14:12
Vertical Flip (aka Mirror)
16:55
Example Graph
17:07
Multiplying the Vertical Component by -1
17:18
Horizontal Flip (aka Mirror)
18:43
Example Graph
19:01
Multiplying the Horizontal Component by -1
19:54
Summary of Transformations
22:11
Stacking Transformations
24:46
Order Matters
25:20
Transformation Example
25:52
Example 1
29:21
Example 2
34:44
Example 3
38:10
Example 4
43:46
Composite Functions

33m 24s

Intro
0:00
Introduction
0:04
Arithmetic Combinations
0:40
Basic Operations
1:20
Definition of the Four Arithmetic Combinations
1:40
Composite Functions
2:53
The Function as a Machine
3:32
Function Compositions as Multiple Machines
3:59
Notation for Composite Functions
4:46
Two Formats
6:02
Another Visual Interpretation
7:17
How to Use Composite Functions
8:21
Example of on Function acting on Another
9:17
Example 1
11:03
Example 2
15:27
Example 3
21:11
Example 4
27:06
Piecewise Functions

51m 42s

Intro
0:00
Introduction
0:04
Analogies to a Piecewise Function
1:16
Different Potatoes
1:41
Factory Production
2:27
Notations for Piecewise Functions
3:39
Notation Examples from Analogies
6:11
Example of a Piecewise (with Table)
7:24
Example of a Non-Numerical Piecewise
11:35
Graphing Piecewise Functions
14:15
Graphing Piecewise Functions, Example
16:26
Continuous Functions
16:57
Statements of Continuity
19:30
Example of Continuous and Non-Continuous Graphs
20:05
Interesting Functions: the Step Function
22:00
Notation for the Step Function
22:40
How the Step Function Works
22:56
Graph of the Step Function
25:30
Example 1
26:22
Example 2
28:49
Example 3
36:50
Example 4
46:11
Inverse Functions

49m 37s

Intro
0:00
Introduction
0:04
Analogy by picture
1:10
How to Denote the inverse
1:40
What Comes out of the Inverse
1:52
Requirement for Reversing
2:02
2:12
The Importance of Information
2:45
One-to-One
4:04
Requirement for Reversibility
4:21
When a Function has an Inverse
4:43
One-to-One
5:13
Not One-to-One
5:50
Not a Function
6:19
Horizontal Line Test
7:01
How to the test Works
7:12
One-to-One
8:12
Not One-to-One
8:45
Definition: Inverse Function
9:12
Formal Definition
9:21
Caution to Students
10:02
Domain and Range
11:12
Finding the Range of the Function Inverse
11:56
Finding the Domain of the Function Inverse
12:11
Inverse of an Inverse
13:09
Its just x!
13:26
Proof
14:03
Graphical Interpretation
17:07
Horizontal Line Test
17:20
Graph of the Inverse
18:04
Swapping Inputs and Outputs to Draw Inverses
19:02
How to Find the Inverse
21:03
What We Are Looking For
21:21
Reversing the Function
21:38
A Method to Find Inverses
22:33
Check Function is One-to-One
23:04
Swap f(x) for y
23:25
Interchange x and y
23:41
Solve for y
24:12
Replace y with the inverse
24:40
25:01
Keeping Step 2 and 3 Straight
25:44
Switching to Inverse
26:12
Checking Inverses
28:52
How to Check an Inverse
29:06
Quick Example of How to Check
29:56
Example 1
31:48
Example 2
34:56
Example 3
39:29
Example 4
46:19
Variation Direct and Inverse

28m 49s

Intro
0:00
Introduction
0:06
Direct Variation
1:14
Same Direction
1:21
Common Example: Groceries
1:56
Different Ways to Say that Two Things Vary Directly
2:28
Basic Equation for Direct Variation
2:55
Inverse Variation
3:40
Opposite Direction
3:50
Common Example: Gravity
4:53
Different Ways to Say that Two Things Vary Indirectly
5:48
Basic Equation for Indirect Variation
6:33
Joint Variation
7:27
Equation for Joint Variation
7:53
Explanation of the Constant
8:48
Combined Variation
9:35
Gas Law as a Combination
9:44
Single Constant
10:33
Example 1
10:49
Example 2
13:34
Example 3
15:39
Example 4
19:48
Section 3: Polynomials
Intro to Polynomials

38m 41s

Intro
0:00
Introduction
0:04
Definition of a Polynomial
1:04
Starting Integer
2:06
Structure of a Polynomial
2:49
The a Constants
3:34
Polynomial Function
5:13
Polynomial Equation
5:23
Polynomials with Different Variables
5:36
Degree
6:23
Informal Definition
6:31
Find the Largest Exponent Variable
6:44
Quick Examples
7:36
Special Names for Polynomials
8:59
Based on the Degree
9:23
Based on the Number of Terms
10:12
Distributive Property (aka 'FOIL')
11:37
Basic Distributive Property
12:21
Distributing Two Binomials
12:55
Longer Parentheses
15:12
Reverse: Factoring
17:26
Long-Term Behavior of Polynomials
17:48
Examples
18:13
Controlling Term--Term with the Largest Exponent
19:33
Positive and Negative Coefficients on the Controlling Term
20:21
22:07
Even Degree, Positive Coefficient
22:13
Even Degree, Negative Coefficient
22:39
Odd Degree, Positive Coefficient
23:09
Odd Degree, Negative Coefficient
23:27
Example 1
25:11
Example 2
27:16
Example 3
31:16
Example 4
34:41
Roots (Zeros) of Polynomials

41m 7s

Intro
0:00
Introduction
0:05
Roots in Graphs
1:17
The x-intercepts
1:33
How to Remember What 'Roots' Are
1:50
Naïve Attempts
2:31
Isolating Variables
2:45
Failures of Isolating Variables
3:30
Missing Solutions
4:59
Factoring: How to Find Roots
6:28
How Factoring Works
6:36
Why Factoring Works
7:20
Steps to Finding Polynomial Roots
9:21
Factoring: How to Find Roots CAUTION
10:08
Factoring is Not Easy
11:32
13:08
13:21
Form of Factored Binomials
13:38
Factoring Examples
14:40
16:58
Factoring Higher Degree Polynomials
18:19
Factoring a Cubic
18:32
19:04
Factoring: Roots Imply Factors
19:54
Where a Root is, A Factor Is
20:01
How to Use Known Roots to Make Factoring Easier
20:35
Not all Polynomials Can be Factored
22:30
Irreducible Polynomials
23:27
Complex Numbers Help
23:55
Max Number of Roots/Factors
24:57
Limit to Number of Roots Equal to the Degree
25:18
Why there is a Limit
25:25
Max Number of Peaks/Valleys
26:39
Shape Information from Degree
26:46
Example Graph
26:54
Max, But Not Required
28:00
Example 1
28:37
Example 2
31:21
Example 3
36:12
Example 4
38:40
Completing the Square and the Quadratic Formula

39m 43s

Intro
0:00
Introduction
0:05
Square Roots and Equations
0:51
Taking the Square Root to Find the Value of x
0:55
Getting the Positive and Negative Answers
1:05
Completing the Square: Motivation
2:04
Polynomials that are Easy to Solve
2:20
Making Complex Polynomials Easy to Solve
3:03
Steps to Completing the Square
4:30
Completing the Square: Method
7:22
Move C over
7:35
Divide by A
7:44
Find r
7:59
Add to Both Sides to Complete the Square
8:49
9:56
11:38
Derivation
11:43
Final Form
12:23
13:38
How Many Roots?
14:53
The Discriminant
15:47
What the Discriminant Tells Us: How Many Roots
15:58
How the Discriminant Works
16:30
Example 1: Complete the Square
18:24
22:00
Example 3: Solve for Zeroes
25:28
Example 4: Using the Quadratic Formula
30:52

45m 34s

Intro
0:00
Introduction
0:05
Parabolas
0:35
Examples of Different Parabolas
1:06
Axis of Symmetry and Vertex
1:28
Drawing an Axis of Symmetry
1:51
Placing the Vertex
2:28
Looking at the Axis of Symmetry and Vertex for other Parabolas
3:09
Transformations
4:18
Reviewing Transformation Rules
6:28
Note the Different Horizontal Shift Form
7:45
8:54
The Constants: k, h, a
9:05
Transformations Formed
10:01
Analyzing Different Parabolas
10:10
Switching Forms by Completing the Square
11:43
Vertex of a Parabola
16:30
Vertex at (h, k)
16:47
Vertex in Terms of a, b, and c Coefficients
17:28
Minimum/Maximum at Vertex
18:19
When a is Positive
18:25
When a is Negative
18:52
Axis of Symmetry
19:54
Incredibly Minor Note on Grammar
20:52
Example 1
21:48
Example 2
26:35
Example 3
28:55
Example 4
31:40
Intermediate Value Theorem and Polynomial Division

46m 8s

Intro
0:00
Introduction
0:05
Reminder: Roots Imply Factors
1:32
The Intermediate Value Theorem
3:41
The Basis: U between a and b
4:11
U is on the Function
4:52
Intermediate Value Theorem, Proof Sketch
5:51
If Not True, the Graph Would Have to Jump
5:58
But Graph is Defined as Continuous
6:43
Finding Roots with the Intermediate Value Theorem
7:01
Picking a and b to be of Different Signs
7:10
Must Be at Least One Root
7:46
Dividing a Polynomial
8:16
Using Roots and Division to Factor
8:38
Long Division Refresher
9:08
The Division Algorithm
12:18
How It Works to Divide Polynomials
12:37
The Parts of the Equation
13:24
Rewriting the Equation
14:47
Polynomial Long Division
16:20
Polynomial Long Division In Action
16:29
One Step at a Time
20:51
Synthetic Division
22:46
Setup
23:11
Synthetic Division, Example
24:44
Which Method Should We Use
26:39
26:49
27:13
Example 1
29:24
Example 2
31:27
Example 3
36:22
Example 4
40:55
Complex Numbers

45m 36s

Intro
0:00
Introduction
0:04
A Wacky Idea
1:02
The Definition of the Imaginary Number
1:22
How it Helps Solve Equations
2:20
Square Roots and Imaginary Numbers
3:15
Complex Numbers
5:00
Real Part and Imaginary Part
5:20
When Two Complex Numbers are Equal
6:10
6:40
Deal with Real and Imaginary Parts Separately
7:36
Two Quick Examples
7:54
Multiplication
9:07
FOIL Expansion
9:14
Note What Happens to the Square of the Imaginary Number
9:41
Two Quick Examples
10:22
Division
11:27
Complex Conjugates
13:37
Getting Rid of i
14:08
How to Denote the Conjugate
14:48
Division through Complex Conjugates
16:11
Multiply by the Conjugate of the Denominator
16:28
Example
17:46
19:24
20:12
Conjugate Pairs
20:37
But Are the Complex Numbers 'Real'?
21:27
What Makes a Number Legitimate
25:38
Where Complex Numbers are Used
27:20
Still, We Won't See Much of C
29:05
Example 1
30:30
Example 2
33:15
Example 3
38:12
Example 4
42:07
Fundamental Theorem of Algebra

19m 9s

Intro
0:00
Introduction
0:05
Idea: Hidden Roots
1:16
Roots in Complex Form
1:42
All Polynomials Have Roots
2:08
Fundamental Theorem of Algebra
2:21
Where Are All the Imaginary Roots, Then?
3:17
All Roots are Complex
3:45
Real Numbers are a Subset of Complex Numbers
3:59
The n Roots Theorem
5:01
For Any Polynomial, Its Degree is Equal to the Number of Roots
5:11
Equivalent Statement
5:24
6:29
Non-Distinct Roots
6:59
Denoting Multiplicity
7:20
7:41
8:55
9:59
Proof Sketch of n Roots Theorem
10:45
First Root
11:36
Second Root
13:23
Continuation to Find all Roots
16:00
Section 4: Rational Functions
Rational Functions and Vertical Asymptotes

33m 22s

Intro
0:00
Introduction
0:05
Definition of a Rational Function
1:20
Examples of Rational Functions
2:30
Why They are Called 'Rational'
2:47
Domain of a Rational Function
3:15
Undefined at Denominator Zeros
3:25
Otherwise all Reals
4:16
Investigating a Fundamental Function
4:50
The Domain of the Function
5:04
What Occurs at the Zeroes of the Denominator
5:20
Idea of a Vertical Asymptote
6:23
What's Going On?
6:58
Approaching x=0 from the left
7:32
Approaching x=0 from the right
8:34
Dividing by Very Small Numbers Results in Very Large Numbers
9:31
Definition of a Vertical Asymptote
10:05
Vertical Asymptotes and Graphs
11:15
Drawing Asymptotes by Using a Dashed Line
11:27
The Graph Can Never Touch Its Undefined Point
12:00
Not All Zeros Give Asymptotes
13:02
Special Cases: When Numerator and Denominator Go to Zero at the Same Time
14:58
Cancel out Common Factors
15:49
How to Find Vertical Asymptotes
16:10
Figure out What Values Are Not in the Domain of x
16:24
Determine if the Numerator and Denominator Share Common Factors and Cancel
16:45
Find Denominator Roots
17:33
Note if Asymptote Approaches Negative or Positive Infinity
18:06
Example 1
18:57
Example 2
21:26
Example 3
23:04
Example 4
30:01
Horizontal Asymptotes

34m 16s

Intro
0:00
Introduction
0:05
Investigating a Fundamental Function
0:53
What Happens as x Grows Large
1:00
Different View
1:12
Idea of a Horizontal Asymptote
1:36
What's Going On?
2:24
What Happens as x Grows to a Large Negative Number
2:49
What Happens as x Grows to a Large Number
3:30
Dividing by Very Large Numbers Results in Very Small Numbers
3:52
Example Function
4:41
Definition of a Vertical Asymptote
8:09
Expanding the Idea
9:03
What's Going On?
9:48
What Happens to the Function in the Long Run?
9:51
Rewriting the Function
10:13
Definition of a Slant Asymptote
12:09
Symbolical Definition
12:30
Informal Definition
12:45
Beyond Slant Asymptotes
13:03
Not Going Beyond Slant Asymptotes
14:39
Horizontal/Slant Asymptotes and Graphs
15:43
How to Find Horizontal and Slant Asymptotes
16:52
How to Find Horizontal Asymptotes
17:12
Expand the Given Polynomials
17:18
Compare the Degrees of the Numerator and Denominator
17:40
How to Find Slant Asymptotes
20:05
Slant Asymptotes Exist When n+m=1
20:08
Use Polynomial Division
20:24
Example 1
24:32
Example 2
25:53
Example 3
26:55
Example 4
29:22
Graphing Asymptotes in a Nutshell

49m 7s

Intro
0:00
Introduction
0:05
A Process for Graphing
1:22
1. Factor Numerator and Denominator
1:50
2. Find Domain
2:53
3. Simplifying the Function
3:59
4. Find Vertical Asymptotes
4:59
5. Find Horizontal/Slant Asymptotes
5:24
6. Find Intercepts
7:35
7. Draw Graph (Find Points as Necessary)
9:21
Draw Graph Example
11:21
Vertical Asymptote
11:41
Horizontal Asymptote
11:50
Other Graphing
12:16
Test Intervals
15:08
Example 1
17:57
Example 2
23:01
Example 3
29:02
Example 4
33:37
Partial Fractions

44m 56s

Intro
0:00
Introduction: Idea
0:04
Introduction: Prerequisites and Uses
1:57
Proper vs. Improper Polynomial Fractions
3:11
Possible Things in the Denominator
4:38
Linear Factors
6:16
Example of Linear Factors
7:03
Multiple Linear Factors
7:48
8:25
9:26
9:49
Mixing Factor Types
10:28
Figuring Out the Numerator
11:10
How to Solve for the Constants
11:30
Quick Example
11:40
Example 1
14:29
Example 2
18:35
Example 3
20:33
Example 4
28:51
Section 5: Exponential & Logarithmic Functions
Understanding Exponents

35m 17s

Intro
0:00
Introduction
0:05
Fundamental Idea
1:46
Expanding the Idea
2:28
Multiplication of the Same Base
2:40
Exponents acting on Exponents
3:45
Different Bases with the Same Exponent
4:31
To the Zero
5:35
To the First
5:45
Fundamental Rule with the Zero Power
6:35
To the Negative
7:45
Any Number to a Negative Power
8:14
A Fraction to a Negative Power
9:58
Division with Exponential Terms
10:41
To the Fraction
11:33
Square Root
11:58
Any Root
12:59
Summary of Rules
14:38
To the Irrational
17:21
Example 1
20:34
Example 2
23:42
Example 3
27:44
Example 4
31:44
Example 5
33:15
Exponential Functions

47m 4s

Intro
0:00
Introduction
0:05
Definition of an Exponential Function
0:48
Definition of the Base
1:02
Restrictions on the Base
1:16
Computing Exponential Functions
2:29
Harder Computations
3:10
When to Use a Calculator
3:21
Graphing Exponential Functions: a>1
6:02
Three Examples
6:13
What to Notice on the Graph
7:44
A Story
8:27
Story Diagram
9:15
Increasing Exponentials
11:29
Story Morals
14:40
Application: Compound Interest
15:15
Compounding Year after Year
16:01
Function for Compounding Interest
16:51
A Special Number: e
20:55
Expression for e
21:28
Where e stabilizes
21:55
Application: Continuously Compounded Interest
24:07
Equation for Continuous Compounding
24:22
Exponential Decay 0<a<1
25:50
Three Examples
26:11
Why they 'lose' value
26:54
Example 1
27:47
Example 2
33:11
Example 3
36:34
Example 4
41:28
Introduction to Logarithms

40m 31s

Intro
0:00
Introduction
0:04
Definition of a Logarithm, Base 2
0:51
Log 2 Defined
0:55
Examples
2:28
Definition of a Logarithm, General
3:23
Examples of Logarithms
5:15
Problems with Unusual Bases
7:38
Shorthand Notation: ln and log
9:44
base e as ln
10:01
base 10 as log
10:34
Calculating Logarithms
11:01
using a calculator
11:34
issues with other bases
11:58
Graphs of Logarithms
13:21
Three Examples
13:29
Slow Growth
15:19
Logarithms as Inverse of Exponentiation
16:02
Using Base 2
16:05
General Case
17:10
Looking More Closely at Logarithm Graphs
19:16
The Domain of Logarithms
20:41
21:08
The Alternate
24:00
Example 1
25:59
Example 2
30:03
Example 3
32:49
Example 4
37:34
Properties of Logarithms

42m 33s

Intro
0:00
Introduction
0:04
Basic Properties
1:12
Inverse--log(exp)
1:43
A Key Idea
2:44
What We Get through Exponentiation
3:18
B Always Exists
4:50
Inverse--exp(log)
5:53
Logarithm of a Power
7:44
Logarithm of a Product
10:07
Logarithm of a Quotient
13:48
Caution! There Is No Rule for loga(M+N)
16:12
Summary of Properties
17:42
Change of Base--Motivation
20:17
No Calculator Button
20:59
A Specific Example
21:45
Simplifying
23:45
Change of Base--Formula
24:14
Example 1
25:47
Example 2
29:08
Example 3
31:14
Example 4
34:13
Solving Exponential and Logarithmic Equations

34m 10s

Intro
0:00
Introduction
0:05
One to One Property
1:09
Exponential
1:26
Logarithmic
1:44
Specific Considerations
2:02
One-to-One Property
3:30
Solving by One-to-One
4:11
Inverse Property
6:09
Solving by Inverses
7:25
Dealing with Equations
7:50
Example of Taking an Exponent or Logarithm of an Equation
9:07
A Useful Property
11:57
Bring Down Exponents
12:01
Try to Simplify
13:20
Extraneous Solutions
13:45
Example 1
16:37
Example 2
19:39
Example 3
21:37
Example 4
26:45
Example 5
29:37
Application of Exponential and Logarithmic Functions

48m 46s

Intro
0:00
Introduction
0:06
Applications of Exponential Functions
1:07
A Secret!
2:17
Natural Exponential Growth Model
3:07
Figure out r
3:34
A Secret!--Why Does It Work?
4:44
e to the r Morphs
4:57
Example
5:06
Applications of Logarithmic Functions
8:32
Examples
8:43
What Logarithms are Useful For
9:53
Example 1
11:29
Example 2
15:30
Example 3
26:22
Example 4
32:05
Example 5
39:19
Section 6: Trigonometric Functions
Angles

39m 5s

Intro
0:00
Degrees
0:22
Circle is 360 Degrees
0:48
Splitting a Circle
1:13
2:08
2:31
2:52
Half-Circle and Right Angle
4:00
6:24
6:52
Coterminal, Complementary, Supplementary Angles
7:23
Coterminal Angles
7:30
Complementary Angles
9:40
Supplementary Angles
10:08
Example 1: Dividing a Circle
10:38
Example 2: Converting Between Degrees and Radians
11:56
Example 3: Quadrants and Coterminal Angles
14:18
Extra Example 1: Common Angle Conversions
-1
Extra Example 2: Quadrants and Coterminal Angles
-2
Sine and Cosine Functions

43m 16s

Intro
0:00
Sine and Cosine
0:15
Unit Circle
0:22
Coordinates on Unit Circle
1:03
Right Triangles
1:52
2:25
Master Right Triangle Formula: SOHCAHTOA
2:48
Odd Functions, Even Functions
4:40
Example: Odd Function
4:56
Example: Even Function
7:30
Example 1: Sine and Cosine
10:27
Example 2: Graphing Sine and Cosine Functions
14:39
Example 3: Right Triangle
21:40
Example 4: Odd, Even, or Neither
26:01
Extra Example 1: Right Triangle
-1
Extra Example 2: Graphing Sine and Cosine Functions
-2
Sine and Cosine Values of Special Angles

33m 5s

Intro
0:00
45-45-90 Triangle and 30-60-90 Triangle
0:08
45-45-90 Triangle
0:21
30-60-90 Triangle
2:06
Mnemonic: All Students Take Calculus (ASTC)
5:21
Using the Unit Circle
5:59
New Angles
6:21
9:43
Mnemonic: All Students Take Calculus
10:13
13:11
16:48
Example 3: All Angles and Quadrants
20:21
Extra Example 1: Convert, Quadrant, Sine/Cosine
-1
Extra Example 2: All Angles and Quadrants
-2
Modified Sine Waves: Asin(Bx+C)+D and Acos(Bx+C)+D

52m 3s

Intro
0:00
Amplitude and Period of a Sine Wave
0:38
Sine Wave Graph
0:58
Amplitude: Distance from Middle to Peak
1:18
Peak: Distance from Peak to Peak
2:41
Phase Shift and Vertical Shift
4:13
Phase Shift: Distance Shifted Horizontally
4:16
Vertical Shift: Distance Shifted Vertically
6:48
Example 1: Amplitude/Period/Phase and Vertical Shift
8:04
Example 2: Amplitude/Period/Phase and Vertical Shift
17:39
Example 3: Find Sine Wave Given Attributes
25:23
Extra Example 1: Amplitude/Period/Phase and Vertical Shift
-1
Extra Example 2: Find Cosine Wave Given Attributes
-2
Tangent and Cotangent Functions

36m 4s

Intro
0:00
Tangent and Cotangent Definitions
0:21
Tangent Definition
0:25
Cotangent Definition
0:47
Master Formula: SOHCAHTOA
1:01
Mnemonic
1:16
Tangent and Cotangent Values
2:29
Remember Common Values of Sine and Cosine
2:46
90 Degrees Undefined
4:36
Slope and Menmonic: ASTC
5:47
Uses of Tangent
5:54
Example: Tangent of Angle is Slope
6:09
7:49
Example 1: Graph Tangent and Cotangent Functions
10:42
Example 2: Tangent and Cotangent of Angles
16:09
Example 3: Odd, Even, or Neither
18:56
Extra Example 1: Tangent and Cotangent of Angles
-1
Extra Example 2: Tangent and Cotangent of Angles
-2
Secant and Cosecant Functions

27m 18s

Intro
0:00
Secant and Cosecant Definitions
0:17
Secant Definition
0:18
Cosecant Definition
0:33
Example 1: Graph Secant Function
0:48
Example 2: Values of Secant and Cosecant
6:49
Example 3: Odd, Even, or Neither
12:49
Extra Example 1: Graph of Cosecant Function
-1
Extra Example 2: Values of Secant and Cosecant
-2
Inverse Trigonometric Functions

32m 58s

Intro
0:00
Arcsine Function
0:24
Restrictions between -1 and 1
0:43
Arcsine Notation
1:26
Arccosine Function
3:07
Restrictions between -1 and 1
3:36
Cosine Notation
3:53
Arctangent Function
4:30
Between -Pi/2 and Pi/2
4:44
Tangent Notation
5:02
Example 1: Domain/Range/Graph of Arcsine
5:45
Example 2: Arcsin/Arccos/Arctan Values
10:46
Example 3: Domain/Range/Graph of Arctangent
17:14
Extra Example 1: Domain/Range/Graph of Arccosine
-1
Extra Example 2: Arcsin/Arccos/Arctan Values
-2
Computations of Inverse Trigonometric Functions

31m 8s

Intro
0:00
Inverse Trigonometric Function Domains and Ranges
0:31
Arcsine
0:41
Arccosine
1:14
Arctangent
1:41
Example 1: Arcsines of Common Values
2:44
Example 2: Odd, Even, or Neither
5:57
Example 3: Arccosines of Common Values
12:24
Extra Example 1: Arctangents of Common Values
-1
Extra Example 2: Arcsin/Arccos/Arctan Values
-2
Section 7: Trigonometric Identities
Pythagorean Identity

19m 11s

Intro
0:00
Pythagorean Identity
0:17
Pythagorean Triangle
0:27
Pythagorean Identity
0:45
Example 1: Use Pythagorean Theorem to Prove Pythagorean Identity
1:14
Example 2: Find Angle Given Cosine and Quadrant
4:18
Example 3: Verify Trigonometric Identity
8:00
Extra Example 1: Use Pythagorean Identity to Prove Pythagorean Theorem
-1
Extra Example 2: Find Angle Given Cosine and Quadrant
-2
Identity Tan(squared)x+1=Sec(squared)x

23m 16s

Intro
0:00
Main Formulas
0:19
Companion to Pythagorean Identity
0:27
For Cotangents and Cosecants
0:52
How to Remember
0:58
Example 1: Prove the Identity
1:40
Example 2: Given Tan Find Sec
3:42
Example 3: Prove the Identity
7:45
Extra Example 1: Prove the Identity
-1
Extra Example 2: Given Sec Find Tan
-2

52m 52s

Intro
0:00
0:09
How to Remember
0:48
Cofunction Identities
1:31
How to Remember Graphically
1:44
Where to Use Cofunction Identities
2:52
Example 1: Derive the Formula for cos(A-B)
3:08
Example 2: Use Addition and Subtraction Formulas
16:03
Example 3: Use Addition and Subtraction Formulas to Prove Identity
25:11
Extra Example 1: Use cos(A-B) and Cofunction Identities
-1
Extra Example 2: Convert to Radians and use Formulas
-2
Double Angle Formulas

29m 5s

Intro
0:00
Main Formula
0:07
How to Remember from Addition Formula
0:18
Two Other Forms
1:35
Example 1: Find Sine and Cosine of Angle using Double Angle
3:16
Example 2: Prove Trigonometric Identity using Double Angle
9:37
Example 3: Use Addition and Subtraction Formulas
12:38
Extra Example 1: Find Sine and Cosine of Angle using Double Angle
-1
Extra Example 2: Prove Trigonometric Identity using Double Angle
-2
Half-Angle Formulas

43m 55s

Intro
0:00
Main Formulas
0:09
Confusing Part
0:34
Example 1: Find Sine and Cosine of Angle using Half-Angle
0:54
Example 2: Prove Trigonometric Identity using Half-Angle
11:51
Example 3: Prove the Half-Angle Formula for Tangents
18:39
Extra Example 1: Find Sine and Cosine of Angle using Half-Angle
-1
Extra Example 2: Prove Trigonometric Identity using Half-Angle
-2
Section 8: Applications of Trigonometry
Trigonometry in Right Angles

25m 43s

Intro
0:00
Master Formula for Right Angles
0:11
SOHCAHTOA
0:15
Only for Right Triangles
1:26
Example 1: Find All Angles in a Triangle
2:19
Example 2: Find Lengths of All Sides of Triangle
7:39
Example 3: Find All Angles in a Triangle
11:00
Extra Example 1: Find All Angles in a Triangle
-1
Extra Example 2: Find Lengths of All Sides of Triangle
-2
Law of Sines

56m 40s

Intro
0:00
Law of Sines Formula
0:18
SOHCAHTOA
0:27
Any Triangle
0:59
Graphical Representation
1:25
Solving Triangle Completely
2:37
When to Use Law of Sines
2:55
ASA, SAA, SSA, AAA
2:59
SAS, SSS for Law of Cosines
7:11
Example 1: How Many Triangles Satisfy Conditions, Solve Completely
8:44
Example 2: How Many Triangles Satisfy Conditions, Solve Completely
15:30
Example 3: How Many Triangles Satisfy Conditions, Solve Completely
28:32
Extra Example 1: How Many Triangles Satisfy Conditions, Solve Completely
-1
Extra Example 2: How Many Triangles Satisfy Conditions, Solve Completely
-2
Law of Cosines

49m 5s

Intro
0:00
Law of Cosines Formula
0:23
Graphical Representation
0:34
Relates Sides to Angles
1:00
Any Triangle
1:20
Generalization of Pythagorean Theorem
1:32
When to Use Law of Cosines
2:26
SAS, SSS
2:30
Heron's Formula
4:49
Semiperimeter S
5:11
Example 1: How Many Triangles Satisfy Conditions, Solve Completely
5:53
Example 2: How Many Triangles Satisfy Conditions, Solve Completely
15:19
Example 3: Find Area of a Triangle Given All Side Lengths
26:33
Extra Example 1: How Many Triangles Satisfy Conditions, Solve Completely
-1
Extra Example 2: Length of Third Side and Area of Triangle
-2
Finding the Area of a Triangle

27m 37s

Intro
0:00
Master Right Triangle Formula and Law of Cosines
0:19
SOHCAHTOA
0:27
Law of Cosines
1:23
Heron's Formula
2:22
Semiperimeter S
2:37
Example 1: Area of Triangle with Two Sides and One Angle
3:12
Example 2: Area of Triangle with Three Sides
6:11
Example 3: Area of Triangle with Three Sides, No Heron's Formula
8:50
Extra Example 1: Area of Triangle with Two Sides and One Angle
-1
Extra Example 2: Area of Triangle with Two Sides and One Angle
-2
Word Problems and Applications of Trigonometry

34m 25s

Intro
0:00
Formulas to Remember
0:11
SOHCAHTOA
0:15
Law of Sines
0:55
Law of Cosines
1:48
Heron's Formula
2:46
Example 1: Telephone Pole Height
4:01
Example 2: Bridge Length
7:48
Example 3: Area of Triangular Field
14:20
Extra Example 1: Kite Height
-1
Extra Example 2: Roads to a Town
-2
Section 9: Systems of Equations and Inequalities
Systems of Linear Equations

55m 40s

Intro
0:00
Introduction
0:04
Graphs as Location of 'True'
1:49
All Locations that Make the Function True
2:25
Understand the Relationship Between Solutions and the Graph
3:43
Systems as Graphs
4:07
Equations as Lines
4:20
Intersection Point
5:19
Three Possibilities for Solutions
6:17
Independent
6:24
Inconsistent
6:36
Dependent
7:06
Solving by Substitution
8:37
Solve for One Variable
9:07
Substitute into the Second Equation
9:34
Solve for Both Variables
10:12
What If a System is Inconsistent or Dependent?
11:08
No Solutions
11:25
Infinite Solutions
12:30
Solving by Elimination
13:56
Example
14:22
Determining the Number of Solutions
16:30
Why Elimination Makes Sense
17:25
Solving by Graphing Calculator
19:59
Systems with More than Two Variables
23:22
Example 1
25:49
Example 2
30:22
Example 3
34:11
Example 4
38:55
Example 5
46:01
(Non-) Example 6
53:37
Systems of Linear Inequalities

1h 13s

Intro
0:00
Introduction
0:04
Inequality Refresher-Solutions
0:46
Equation Solutions vs. Inequality Solutions
1:02
Essentially a Wide Variety of Answers
1:35
Refresher--Negative Multiplication Flips
1:43
Refresher--Negative Flips: Why?
3:19
Multiplication by a Negative
3:43
The Relationship Flips
3:55
Refresher--Stick to Basic Operations
4:34
Linear Equations in Two Variables
6:50
Graphing Linear Inequalities
8:28
Why It Includes a Whole Section
8:43
How to Show The Difference Between Strict and Not Strict Inequalities
10:08
Dashed Line--Not Solutions
11:10
Solid Line--Are Solutions
11:24
11:42
Example of Using a Point
12:41
13:14
Graphing a System
14:53
Set of Solutions is the Overlap
15:17
Example
15:22
Solutions are Best Found Through Graphing
18:05
Linear Programming-Idea
19:52
Use a Linear Objective Function
20:15
Variables in Objective Function have Constraints
21:24
Linear Programming-Method
22:09
Rearrange Equations
22:21
Graph
22:49
Critical Solution is at the Vertex of the Overlap
23:40
Try Each Vertice
24:35
Example 1
24:58
Example 2
28:57
Example 3
33:48
Example 4
43:10
Nonlinear Systems

41m 1s

Intro
0:00
Introduction
0:06
Substitution
1:12
Example
1:22
Elimination
3:46
Example
3:56
Elimination is Less Useful for Nonlinear Systems
4:56
Graphing
5:56
Using a Graphing Calculator
6:44
Number of Solutions
8:44
Systems of Nonlinear Inequalities
10:02
Graph Each Inequality
10:06
Dashed and/or Solid
10:18
11:14
Example 1
13:24
Example 2
15:50
Example 3
22:02
Example 4
29:06
Example 4, cont.
33:40
Section 10: Vectors and Matrices
Vectors

1h 9m 31s

Intro
0:00
Introduction
0:10
Magnitude of the Force
0:22
Direction of the Force
0:48
Vector
0:52
Idea of a Vector
1:30
How Vectors are Denoted
2:00
Component Form
3:20
Angle Brackets and Parentheses
3:50
Magnitude/Length
4:26
Denoting the Magnitude of a Vector
5:16
Direction/Angle
7:52
Always Draw a Picture
8:50
Component Form from Magnitude & Angle
10:10
Scaling by Scalars
14:06
Unit Vectors
16:26
Combining Vectors - Algebraically
18:10
Combining Vectors - Geometrically
19:54
Resultant Vector
20:46
Alternate Component Form: i, j
21:16
The Zero Vector
23:18
Properties of Vectors
24:20
No Multiplication (Between Vectors)
28:30
Dot Product
29:40
Motion in a Medium
30:10
Fish in an Aquarium Example
31:38
More Than Two Dimensions
33:12
More Than Two Dimensions - Magnitude
34:18
Example 1
35:26
Example 2
38:10
Example 3
45:48
Example 4
50:40
Example 4, cont.
56:07
Example 5
1:01:32
Dot Product & Cross Product

35m 20s

Intro
0:00
Introduction
0:08
Dot Product - Definition
0:42
Dot Product Results in a Scalar, Not a Vector
2:10
Example in Two Dimensions
2:34
Angle and the Dot Product
2:58
The Dot Product of Two Vectors is Deeply Related to the Angle Between the Two Vectors
2:59
Proof of Dot Product Formula
4:14
Won't Directly Help Us Better Understand Vectors
4:18
Dot Product - Geometric Interpretation
4:58
We Can Interpret the Dot Product as a Measure of How Long and How Parallel Two Vectors Are
7:26
Dot Product - Perpendicular Vectors
8:24
If the Dot Product of Two Vectors is 0, We Know They are Perpendicular to Each Other
8:54
Cross Product - Definition
11:08
Cross Product Only Works in Three Dimensions
11:09
Cross Product - A Mnemonic
12:16
The Determinant of a 3 x 3 Matrix and Standard Unit Vectors
12:17
Cross Product - Geometric Interpretations
14:30
The Right-Hand Rule
15:17
Cross Product - Geometric Interpretations Cont.
17:00
Example 1
18:40
Example 2
22:50
Example 3
24:04
Example 4
26:20
Bonus Round
29:18
Proof: Dot Product Formula
29:24
Proof: Dot Product Formula, cont.
30:38
Matrices

54m 7s

Intro
0:00
Introduction
0:08
Definition of a Matrix
3:02
Size or Dimension
3:58
Square Matrix
4:42
Denoted by Capital Letters
4:56
When are Two Matrices Equal?
5:04
Examples of Matrices
6:44
Rows x Columns
6:46
7:48
We Use Capitals to Denote a Matrix and Lower Case to Denotes Its Entries
8:32
Using Entries to Talk About Matrices
10:08
Scalar Multiplication
11:26
Scalar = Real Number
11:34
Example
12:36
13:08
Example
14:22
Matrix Multiplication
15:00
Example
18:52
Matrix Multiplication, cont.
19:58
Matrix Multiplication and Order (Size)
25:26
Make Sure Their Orders are Compatible
25:27
Matrix Multiplication is NOT Commutative
28:20
Example
30:08
Special Matrices - Zero Matrix (0)
32:48
Zero Matrix Has 0 for All of its Entries
32:49
Special Matrices - Identity Matrix (I)
34:14
Identity Matrix is a Square Matrix That Has 1 for All Its Entries on the Main Diagonal and 0 for All Other Entries
34:15
Example 1
36:16
Example 2
40:00
Example 3
44:54
Example 4
50:08
Determinants & Inverses of Matrices

47m 12s

Intro
0:00
Introduction
0:06
Not All Matrices Are Invertible
1:30
What Must a Matrix Have to Be Invertible?
2:08
Determinant
2:32
The Determinant is a Real Number Associated With a Square Matrix
2:38
If the Determinant of a Matrix is Nonzero, the Matrix is Invertible
3:40
Determinant of a 2 x 2 Matrix
4:34
Think in Terms of Diagonals
5:12
Minors and Cofactors - Minors
6:24
Example
6:46
Minors and Cofactors - Cofactors
8:00
Cofactor is Closely Based on the Minor
8:01
Alternating Sign Pattern
9:04
Determinant of Larger Matrices
10:56
Example
13:00
Alternative Method for 3x3 Matrices
16:46
Not Recommended
16:48
Inverse of a 2 x 2 Matrix
19:02
Inverse of Larger Matrices
20:00
Using Inverse Matrices
21:06
When Multiplied Together, They Create the Identity Matrix
21:24
Example 1
23:45
Example 2
27:21
Example 3
32:49
Example 4
36:27
Finding the Inverse of Larger Matrices
41:59
General Inverse Method - Step 1
43:25
General Inverse Method - Step 2
43:27
General Inverse Method - Step 2, cont.
43:27
General Inverse Method - Step 3
45:15
Using Matrices to Solve Systems of Linear Equations

58m 34s

Intro
0:00
Introduction
0:12
Augmented Matrix
1:44
We Can Represent the Entire Linear System With an Augmented Matrix
1:50
Row Operations
3:22
Interchange the Locations of Two Rows
3:50
Multiply (or Divide) a Row by a Nonzero Number
3:58
Add (or Subtract) a Multiple of One Row to Another
4:12
Row Operations - Keep Notes!
5:50
Suggested Symbols
7:08
Gauss-Jordan Elimination - Idea
8:04
Gauss-Jordan Elimination - Idea, cont.
9:16
Reduced Row-Echelon Form
9:18
Gauss-Jordan Elimination - Method
11:36
Begin by Writing the System As An Augmented Matrix
11:38
Gauss-Jordan Elimination - Method, cont.
13:48
Cramer's Rule - 2 x 2 Matrices
17:08
Cramer's Rule - n x n Matrices
19:24
Solving with Inverse Matrices
21:10
Solving Inverse Matrices, cont.
25:28
The Mighty (Graphing) Calculator
26:38
Example 1
29:56
Example 2
33:56
Example 3
37:00
Example 3, cont.
45:04
Example 4
51:28
Section 11: Alternate Ways to Graph
Parametric Equations

53m 33s

Intro
0:00
Introduction
0:06
Definition
1:10
Plane Curve
1:24
The Key Idea
2:00
Graphing with Parametric Equations
2:52
Same Graph, Different Equations
5:04
How Is That Possible?
5:36
Same Graph, Different Equations, cont.
5:42
Here's Another to Consider
7:56
Same Plane Curve, But Still Different
8:10
A Metaphor for Parametric Equations
9:36
Think of Parametric Equations As a Way to Describe the Motion of An Object
9:38
Graph Shows Where It Went, But Not Speed
10:32
Eliminating Parameters
12:14
Rectangular Equation
12:16
Caution
13:52
Creating Parametric Equations
14:30
Interesting Graphs
16:38
Graphing Calculators, Yay!
19:18
Example 1
22:36
Example 2
28:26
Example 3
37:36
Example 4
41:00
Projectile Motion
44:26
Example 5
47:00
Polar Coordinates

48m 7s

Intro
0:00
Introduction
0:04
Polar Coordinates Give Us a Way To Describe the Location of a Point
0:26
Polar Equations and Functions
0:50
Plotting Points with Polar Coordinates
1:06
The Distance of the Point from the Origin
1:09
The Angle of the Point
1:33
Give Points as the Ordered Pair (r,θ)
2:03
Visualizing Plotting in Polar Coordinates
2:32
First Way We Can Plot
2:39
Second Way We Can Plot
2:50
First, We'll Look at Visualizing r, Then θ
3:09
Rotate the Length Counter-Clockwise by θ
3:38
Alternatively, We Can Visualize θ, Then r
4:06
'Polar Graph Paper'
6:17
Horizontal and Vertical Tick Marks Are Not Useful for Polar
6:42
Use Concentric Circles to Helps Up See Distance From the Pole
7:08
Can Use Arc Sectors to See Angles
7:57
Multiple Ways to Name a Point
9:17
Examples
9:30
For Any Angle θ, We Can Make an Equivalent Angle
10:44
Negative Values for r
11:58
If r Is Negative, We Go In The Direction Opposite the One That The Angle θ Points Out
12:22
Another Way to Name the Same Point: Add π to θ and Make r Negative
13:44
Converting Between Rectangular and Polar
14:37
Rectangular Way to Name
14:43
Polar Way to Name
14:52
The Rectangular System Must Have a Right Angle Because It's Based on a Rectangle
15:08
Connect Both Systems Through Basic Trigonometry
15:38
Equation to Convert From Polar to Rectangular Coordinate Systems
16:55
Equation to Convert From Rectangular to Polar Coordinate Systems
17:13
Converting to Rectangular is Easy
17:20
Converting to Polar is a Bit Trickier
17:21
Draw Pictures
18:55
Example 1
19:50
Example 2
25:17
Example 3
31:05
Example 4
35:56
Example 5
41:49
Polar Equations & Functions

38m 16s

Intro
0:00
Introduction
0:04
Equations and Functions
1:16
Independent Variable
1:21
Dependent Variable
1:30
Examples
1:46
Always Assume That θ Is In Radians
2:44
Graphing in Polar Coordinates
3:29
Graph is the Same Way We Graph 'Normal' Stuff
3:32
Example
3:52
Graphing in Polar - Example, Cont.
6:45
Tips for Graphing
9:23
Notice Patterns
10:19
Repetition
13:39
Graphing Equations of One Variable
14:39
Converting Coordinate Types
16:16
Use the Same Conversion Formulas From the Previous Lesson
16:23
Interesting Graphs
17:48
Example 1
18:03
Example 2
18:34
Graphing Calculators, Yay!
19:07
Plot Random Things, Alter Equations You Understand, Get a Sense for How Polar Stuff Works
19:11
Check Out the Appendix
19:26
Example 1
21:36
Example 2
28:13
Example 3
34:24
Example 4
35:52
Section 12: Complex Numbers and Polar Coordinates
Polar Form of Complex Numbers

40m 43s

Intro
0:00
Polar Coordinates
0:49
Rectangular Form
0:52
Polar Form
1:25
R and Theta
1:51
Polar Form Conversion
2:27
R and Theta
2:35
Optimal Values
4:05
Euler's Formula
4:25
Multiplying Two Complex Numbers in Polar Form
6:10
Multiply r's Together and Add Exponents
6:32
Example 1: Convert Rectangular to Polar Form
7:17
Example 2: Convert Polar to Rectangular Form
13:49
Example 3: Multiply Two Complex Numbers
17:28
Extra Example 1: Convert Between Rectangular and Polar Forms
-1
Extra Example 2: Simplify Expression to Polar Form
-2
DeMoivre's Theorem

57m 37s

Intro
0:00
Introduction to DeMoivre's Theorem
0:10
n nth Roots
3:06
DeMoivre's Theorem: Finding nth Roots
3:52
Relation to Unit Circle
6:29
One nth Root for Each Value of k
7:11
Example 1: Convert to Polar Form and Use DeMoivre's Theorem
8:24
Example 2: Find Complex Eighth Roots
15:27
Example 3: Find Complex Roots
27:49
Extra Example 1: Convert to Polar Form and Use DeMoivre's Theorem
-1
Extra Example 2: Find Complex Fourth Roots
-2
Section 13: Counting & Probability
Counting

31m 36s

Intro
0:00
Introduction
0:08
Combinatorics
0:56
Definition: Event
1:24
Example
1:50
Visualizing an Event
3:02
Branching line diagram
3:06
3:40
Example
4:18
Multiplication Principle
5:42
Example
6:24
Pigeonhole Principle
8:06
Example
10:26
Draw Pictures
11:06
Example 1
12:02
Example 2
14:16
Example 3
17:34
Example 4
21:26
Example 5
25:14
Permutations & Combinations

44m 3s

Intro
0:00
Introduction
0:08
Permutation
0:42
Combination
1:10
Towards a Permutation Formula
2:38
How Many Ways Can We Arrange the Letters A, B, C, D, and E?
3:02
Towards a Permutation Formula, cont.
3:34
Factorial Notation
6:56
Symbol Is '!'
6:58
Examples
7:32
Permutation of n Objects
8:44
Permutation of r Objects out of n
9:04
What If We Have More Objects Than We Have Slots to Fit Them Into?
9:46
Permutation of r Objects Out of n, cont.
10:28
Distinguishable Permutations
14:46
What If Not All Of the Objects We're Permuting Are Distinguishable From Each Other?
14:48
Distinguishable Permutations, cont.
17:04
Combinations
19:04
Combinations, cont.
20:56
Example 1
23:10
Example 2
26:16
Example 3
28:28
Example 4
31:52
Example 5
33:58
Example 6
36:34
Probability

36m 58s

Intro
0:00
Introduction
0:06
Definition: Sample Space
1:18
Event = Something Happening
1:20
Sample Space
1:36
Probability of an Event
2:12
Let E Be An Event and S Be The Corresponding Sample Space
2:14
'Equally Likely' Is Important
3:52
Fair and Random
5:26
Interpreting Probability
6:34
How Can We Interpret This Value?
7:24
We Can Represent Probability As a Fraction, a Decimal, Or a Percentage
8:04
One of Multiple Events Occurring
9:52
Mutually Exclusive Events
10:38
What If The Events Are Not Mutually Exclusive?
12:20
Taking the Possibility of Overlap Into Account
13:24
An Event Not Occurring
17:14
Complement of E
17:22
Independent Events
19:36
Independent
19:48
Conditional Events
21:28
What Is The Events Are Not Independent Though?
21:30
Conditional Probability
22:16
Conditional Events, cont.
23:51
Example 1
25:27
Example 2
27:09
Example 3
28:57
Example 4
30:51
Example 5
34:15
Section 14: Conic Sections
Parabolas

41m 27s

Intro
0:00
What is a Parabola?
0:20
Definition of a Parabola
0:29
Focus
0:59
Directrix
1:15
Axis of Symmetry
3:08
Vertex
3:33
Minimum or Maximum
3:44
Standard Form
4:59
Horizontal Parabolas
5:08
Vertex Form
5:19
Upward or Downward
5:41
Example: Standard Form
6:06
Graphing Parabolas
8:31
Shifting
8:51
Example: Completing the Square
9:22
Symmetry and Translation
12:18
Example: Graph Parabola
12:40
Latus Rectum
17:13
Length
18:15
Example: Latus Rectum
18:35
Horizontal Parabolas
18:57
Not Functions
20:08
Example: Horizontal Parabola
21:21
Focus and Directrix
24:11
Horizontal
24:48
Example 1: Parabola Standard Form
25:12
Example 2: Graph Parabola
30:00
Example 3: Graph Parabola
33:13
Example 4: Parabola Equation
37:28
Circles

21m 3s

Intro
0:00
What are Circles?
0:08
Example: Equidistant
0:17
0:32
Equation of a Circle
0:44
Example: Standard Form
1:11
Graphing Circles
1:47
Example: Circle
1:56
Center Not at Origin
3:07
Example: Completing the Square
3:51
Example 1: Equation of Circle
6:44
11:51
15:08
Example 4: Equation of Circle
16:57
Ellipses

46m 51s

Intro
0:00
What Are Ellipses?
0:11
Foci
0:23
Properties of Ellipses
1:43
Major Axis, Minor Axis
1:47
Center
1:54
Length of Major Axis and Minor Axis
3:21
Standard Form
5:33
Example: Standard Form of Ellipse
6:09
Vertical Major Axis
9:14
Example: Vertical Major Axis
9:46
Graphing Ellipses
12:51
Complete the Square and Symmetry
13:00
Example: Graphing Ellipse
13:16
Equation with Center at (h, k)
19:57
Horizontal and Vertical
20:14
Difference
20:27
Example: Center at (h, k)
20:55
Example 1: Equation of Ellipse
24:05
Example 2: Equation of Ellipse
27:57
Example 3: Equation of Ellipse
32:32
Example 4: Graph Ellipse
38:27
Hyperbolas

38m 15s

Intro
0:00
What are Hyperbolas?
0:12
Two Branches
0:18
Foci
0:38
Properties
2:00
Transverse Axis and Conjugate Axis
2:06
Vertices
2:46
Length of Transverse Axis
3:14
Distance Between Foci
3:31
Length of Conjugate Axis
3:38
Standard Form
5:45
Vertex Location
6:36
Known Points
6:52
Vertical Transverse Axis
7:26
Vertex Location
7:50
Asymptotes
8:36
Vertex Location
8:56
Rectangle
9:28
Diagonals
10:29
Graphing Hyperbolas
12:58
Example: Hyperbola
13:16
Equation with Center at (h, k)
16:32
Example: Center at (h, k)
17:21
Example 1: Equation of Hyperbola
19:20
Example 2: Equation of Hyperbola
22:48
Example 3: Graph Hyperbola
26:05
Example 4: Equation of Hyperbola
36:29
Conic Sections

18m 43s

Intro
0:00
Conic Sections
0:16
Double Cone Sections
0:24
Standard Form
1:27
General Form
1:37
Identify Conic Sections
2:16
B = 0
2:50
X and Y
3:22
Identify Conic Sections, Cont.
4:46
Parabola
5:17
Circle
5:51
Ellipse
6:31
Hyperbola
7:10
Example 1: Identify Conic Section
8:01
Example 2: Identify Conic Section
11:03
Example 3: Identify Conic Section
11:38
Example 4: Identify Conic Section
14:50
Section 15: Sequences, Series, & Induction
Introduction to Sequences

57m 45s

Intro
0:00
Introduction
0:06
Definition: Sequence
0:28
Infinite Sequence
2:08
Finite Sequence
2:22
Length
2:58
Formula for the nth Term
3:22
Defining a Sequence Recursively
5:54
Initial Term
7:58
Sequences and Patterns
10:40
First, Identify a Pattern
12:52
How to Get From One Term to the Next
17:38
Tips for Finding Patterns
19:52
More Tips for Finding Patterns
24:14
Even More Tips
26:50
Example 1
30:32
Example 2
34:54
Fibonacci Sequence
34:55
Example 3
38:40
Example 4
45:02
Example 5
49:26
Example 6
51:54
Introduction to Series

40m 27s

Intro
0:00
Introduction
0:06
Definition: Series
1:20
Why We Need Notation
2:48
Simga Notation (AKA Summation Notation)
4:44
Thing Being Summed
5:42
Index of Summation
6:21
Lower Limit of Summation
7:09
Upper Limit of Summation
7:23
Sigma Notation, Example
7:36
Sigma Notation for Infinite Series
9:08
How to Reindex
10:58
How to Reindex, Expanding
12:56
How to Reindex, Substitution
16:46
Properties of Sums
19:42
Example 1
23:46
Example 2
25:34
Example 3
27:12
Example 4
29:54
Example 5
32:06
Example 6
37:16
Arithmetic Sequences & Series

31m 36s

Intro
0:00
Introduction
0:05
Definition: Arithmetic Sequence
0:47
Common Difference
1:13
Two Examples
1:19
Form for the nth Term
2:14
Recursive Relation
2:33
Towards an Arithmetic Series Formula
5:12
Creating a General Formula
10:09
General Formula for Arithmetic Series
14:23
Example 1
15:46
Example 2
17:37
Example 3
22:21
Example 4
24:09
Example 5
27:14
Geometric Sequences & Series

39m 27s

Intro
0:00
Introduction
0:06
Definition
0:48
Form for the nth Term
2:42
Formula for Geometric Series
5:16
Infinite Geometric Series
11:48
Diverges
13:04
Converges
14:48
Formula for Infinite Geometric Series
16:32
Example 1
20:32
Example 2
22:02
Example 3
26:00
Example 4
30:48
Example 5
34:28
Mathematical Induction

49m 53s

Intro
0:00
Introduction
0:06
Belief Vs. Proof
1:22
A Metaphor for Induction
6:14
The Principle of Mathematical Induction
11:38
Base Case
13:24
Inductive Step
13:30
Inductive Hypothesis
13:52
A Remark on Statements
14:18
Using Mathematical Induction
16:58
Working Example
19:58
Finding Patterns
28:46
Example 1
30:17
Example 2
37:50
Example 3
42:38
The Binomial Theorem

1h 13m 13s

Intro
0:00
Introduction
0:06
We've Learned That a Binomial Is An Expression That Has Two Terms
0:07
Understanding Binomial Coefficients
1:20
Things We Notice
2:24
What Goes In the Blanks?
5:52
Each Blank is Called a Binomial Coefficient
6:18
The Binomial Theorem
6:38
Example
8:10
The Binomial Theorem, cont.
10:46
We Can Also Write This Expression Compactly Using Sigma Notation
12:06
Proof of the Binomial Theorem
13:22
Proving the Binomial Theorem Is Within Our Reach
13:24
Pascal's Triangle
15:12
Pascal's Triangle, cont.
16:12
16:24
Zeroth Row
18:04
First Row
18:12
Why Do We Care About Pascal's Triangle?
18:50
Pascal's Triangle, Example
19:26
Example 1
21:26
Example 2
24:34
Example 3
28:34
Example 4
32:28
Example 5
37:12
Time for the Fireworks!
43:38
Proof of the Binomial Theorem
43:44
We'll Prove This By Induction
44:04
Proof (By Induction)
46:36
Proof, Base Case
47:00
Proof, Inductive Step - Notation Discussion
49:22
Induction Step
49:24
Proof, Inductive Step - Setting Up
52:26
Induction Hypothesis
52:34
What We What To Show
52:44
Proof, Inductive Step - Start
54:18
Proof, Inductive Step - Middle
55:38
Expand Sigma Notations
55:48
Proof, Inductive Step - Middle, cont.
58:40
Proof, Inductive Step - Checking In
1:01:08
Let's Check In With Our Original Goal
1:01:12
Want to Show
1:01:18
Lemma - A Mini Theorem
1:02:18
Proof, Inductive Step - Lemma
1:02:52
Proof of Lemma: Let's Investigate the Left Side
1:03:08
Proof, Inductive Step - Nearly There
1:07:54
Proof, Inductive Step - End!
1:09:18
Proof, Inductive Step - End!, cont.
1:11:01
Section 16: Preview of Calculus
Idea of a Limit

40m 22s

Intro
0:00
Introduction
0:05
Motivating Example
1:26
Fuzzy Notion of a Limit
3:38
Limit is the Vertical Location a Function is Headed Towards
3:44
Limit is What the Function Output is Going to Be
4:15
Limit Notation
4:33
Exploring Limits - 'Ordinary' Function
5:26
Test Out
5:27
Graphing, We See The Answer Is What We Would Expect
5:44
Exploring Limits - Piecewise Function
6:45
If We Modify the Function a Bit
6:49
Exploring Limits - A Visual Conception
10:08
Definition of a Limit
12:07
If f(x) Becomes Arbitrarily Close to Some Number L as x Approaches Some Number c, Then the Limit of f(x) As a Approaches c is L.
12:09
We Are Not Concerned with f(x) at x=c
12:49
We Are Considering x Approaching From All Directions, Not Just One Side
13:10
Limits Do Not Always Exist
15:47
Finding Limits
19:49
Graphs
19:52
Tables
21:48
Precise Methods
24:53
Example 1
26:06
Example 2
27:39
Example 3
30:51
Example 4
33:11
Example 5
37:07
Formal Definition of a Limit

57m 11s

Intro
0:00
Introduction
0:06
New Greek Letters
2:42
Delta
3:14
Epsilon
3:46
Sometimes Called the Epsilon-Delta Definition of a Limit
3:56
Formal Definition of a Limit
4:22
What does it MEAN!?!?
5:00
The Groundwork
5:38
Set Up the Limit
5:39
The Function is Defined Over Some Portion of the Reals
5:58
The Horizontal Location is the Value the Limit Will Approach
6:28
The Vertical Location L is Where the Limit Goes To
7:00
The Epsilon-Delta Part
7:26
The Hard Part is the Second Part of the Definition
7:30
Second Half of Definition
10:04
Restrictions on the Allowed x Values
10:28
The Epsilon-Delta Part, cont.
13:34
Sherlock Holmes and Dr. Watson
15:08
The Adventure of the Delta-Epsilon Limit
15:16
Setting
15:18
We Begin By Setting Up the Game As Follows
15:52
The Adventure of the Delta-Epsilon, cont.
17:24
17:46
What If I Try Larger?
19:39
Technically, You Haven't Proven the Limit
20:53
Here is the Method
21:18
What We Should Concern Ourselves With
22:20
Investigate the Left Sides of the Expressions
25:24
We Can Create the Following Inequalities
28:08
Finally…
28:50
Nothing Like a Good Proof to Develop the Appetite
30:42
Example 1
31:02
Example 1, cont.
36:26
Example 2
41:46
Example 2, cont.
47:50
Finding Limits

32m 40s

Intro
0:00
Introduction
0:08
Method - 'Normal' Functions
2:04
The Easiest Limits to Find
2:06
It Does Not 'Break'
2:18
It Is Not Piecewise
2:26
Method - 'Normal' Functions, Example
3:38
Method - 'Normal' Functions, cont.
4:54
The Functions We're Used to Working With Go Where We Expect Them To Go
5:22
5:42
Method - Canceling Factors
7:18
One Weird Thing That Often Happens is Dividing By 0
7:26
Method - Canceling Factors, cont.
8:16
Notice That The Two Functions Are Identical With the Exception of x=0
8:20
Method - Canceling Factors, cont.
10:00
Example
10:52
Method - Rationalization
12:04
Rationalizing a Portion of Some Fraction
12:05
Conjugate
12:26
Method - Rationalization, cont.
13:14
Example
13:50
Method - Piecewise
16:28
The Limits of Piecewise Functions
16:30
Example 1
17:42
Example 2
18:44
Example 3
20:20
Example 4
22:24
Example 5
24:24
Example 6
27:12
Continuity & One-Sided Limits

32m 43s

Intro
0:00
Introduction
0:06
Motivating Example
0:56
Continuity - Idea
2:14
Continuous Function
2:18
All Parts of Function Are Connected
2:28
Function's Graph Can Be Drawn Without Lifting Pencil
2:36
There Are No Breaks or Holes in Graph
2:56
Continuity - Idea, cont.
3:38
We Can Interpret the Break in the Continuity of f(x) as an Issue With the Function 'Jumping'
3:52
Continuity - Definition
5:16
A Break in Continuity is Caused By the Limit Not Matching Up With What the Function Does
5:18
Discontinuous
6:02
Discontinuity
6:10
Continuity and 'Normal' Functions
6:48
Return of the Motivating Example
8:14
One-Sided Limit
8:48
One-Sided Limit - Definition
9:16
Only Considers One Side
9:20
Be Careful to Keep Track of Which Symbol Goes With Which Side
10:06
One-Sided Limit - Example
10:50
There Does Not Necessarily Need to Be a Connection Between Left or Right Side Limits
11:16
Normal Limits and One-Sided Limits
12:08
Limits of Piecewise Functions
14:12
'Breakover' Points
14:22
We Find the Limit of a Piecewise Function By Checking If the Left and Right Side Limits Agree With Each Other
15:34
Example 1
16:40
Example 2
18:54
Example 3
22:00
Example 4
26:36
Limits at Infinity & Limits of Sequences

32m 49s

Intro
0:00
Introduction
0:06
Definition: Limit of a Function at Infinity
1:44
A Limit at Infinity Works Very Similarly to How a Normal Limit Works
2:38
Evaluating Limits at Infinity
4:08
Rational Functions
4:17
Examples
4:30
For a Rational Function, the Question Boils Down to Comparing the Long Term Growth Rates of the Numerator and Denominator
5:22
There are Three Possibilities
6:36
Evaluating Limits at Infinity, cont.
8:08
Does the Function Grow Without Bound? Will It 'Settle Down' Over Time?
10:06
10:26
Limit of a Sequence
12:20
What Value Does the Sequence Tend to Do in the Long-Run?
12:41
The Limit of a Sequence is Very Similar to the Limit of a Function at Infinity
12:52
Numerical Evaluation
14:16
Numerically: Plug in Numbers and See What Comes Out
14:24
Example 1
16:42
Example 2
21:00
Example 3
22:08
Example 4
26:14
Example 5
28:10
Example 6
31:06
Instantaneous Slope & Tangents (Derivatives)

51m 13s

Intro
0:00
Introduction
0:08
The Derivative of a Function Gives Us a Way to Talk About 'How Fast' the Function If Changing
0:16
Instantaneous Slop
0:22
Instantaneous Rate of Change
0:28
Slope
1:24
The Vertical Change Divided by the Horizontal
1:40
Idea of Instantaneous Slope
2:10
What If We Wanted to Apply the Idea of Slope to a Non-Line?
2:14
Tangent to a Circle
3:52
What is the Tangent Line for a Circle?
4:42
Tangent to a Curve
5:20
Towards a Derivative - Average Slope
6:36
Towards a Derivative - Average Slope, cont.
8:20
An Approximation
11:24
Towards a Derivative - General Form
13:18
Towards a Derivative - General Form, cont.
16:46
An h Grows Smaller, Our Slope Approximation Becomes Better
18:44
Towards a Derivative - Limits!
20:04
Towards a Derivative - Limits!, cont.
22:08
We Want to Show the Slope at x=1
22:34
Towards a Derivative - Checking Our Slope
23:12
Definition of the Derivative
23:54
Derivative: A Way to Find the Instantaneous Slope of a Function at Any Point
23:58
Differentiation
24:54
Notation for the Derivative
25:58
The Derivative is a Very Important Idea In Calculus
26:04
The Important Idea
27:34
Why Did We Learn the Formal Definition to Find a Derivative?
28:18
Example 1
30:50
Example 2
36:06
Example 3
40:24
The Power Rule
44:16
Makes It Easier to Find the Derivative of a Function
44:24
Examples
45:04
n Is Any Constant Number
45:46
Example 4
46:26
Area Under a Curve (Integrals)

45m 26s

Intro
0:00
Introduction
0:06
Integral
0:12
Idea of Area Under a Curve
1:18
Approximation by Rectangles
2:12
The Easiest Way to Find Area is With a Rectangle
2:18
Various Methods for Choosing Rectangles
4:30
Rectangle Method - Left-Most Point
5:12
The Left-Most Point
5:16
Rectangle Method - Right-Most Point
5:58
The Right-Most Point
6:00
Rectangle Method - Mid-Point
6:42
Horizontal Mid-Point
6:48
Rectangle Method - Maximum (Upper Sum)
7:34
Maximum Height
7:40
Rectangle Method - Minimum
8:54
Minimum Height
9:02
Evaluating the Area Approximation
10:08
Split the Interval Into n Sub-Intervals
10:30
More Rectangles, Better Approximation
12:14
The More We Us , the Better Our Approximation Becomes
12:16
Our Approximation Becomes More Accurate as the Number of Rectangles n Goes Off to Infinity
12:44
Finding Area with a Limit
13:08
If This Limit Exists, It Is Called the Integral From a to b
14:08
The Process of Finding Integrals is Called Integration
14:22
The Big Reveal
14:40
The Integral is Based on the Antiderivative
14:46
The Big Reveal - Wait, Why?
16:28
The Rate of Change for the Area is Based on the Height of the Function
16:50
Height is the Derivative of Area, So Area is Based on the Antiderivative of Height
17:50
Example 1
19:06
Example 2
22:48
Example 3
29:06
Example 3, cont.
35:14
Example 4
40:14
Section 17: Appendix: Graphing Calculators

10m 41s

Intro
0:00
0:06
Should I Get a Graphing Utility?
0:20
Free Graphing Utilities - Web Based
0:38
Personal Favorite: Desmos
0:58
Free Graphing Utilities - Offline Programs
1:18
GeoGebra
1:31
Microsoft Mathematics
1:50
Grapher
2:18
Other Graphing Utilities - Tablet/Phone
2:48
Should You Buy a Graphing Calculator?
3:22
The Only Real Downside
4:10
4:20
If You Plan on Continuing in Math and/or Science
4:26
If Money is Not Particularly Tight for You
4:32
If You Don't Plan to Continue in Math and Science
5:02
If You Do Plan to Continue and Money Is Tight
5:28
5:44
Which Graphing Calculator is Best?
5:46
Too Many Factors
5:54
6:12
The Old Standby
7:10
TI-83 (Plus)
7:16
TI-84 (Plus)
7:18
9:17
9:19
9:35
10:09
Graphing Calculator Basics

10m 51s

Intro
0:00
0:06
Skim It
0:20
Play Around and Experiment
0:34
Syntax
0:40
Definition of Syntax in English and Math
0:46
Pay Careful Attention to Your Syntax When Working With a Calculator
2:08
Make Sure You Use Parentheses to Indicate the Proper Order of Operations
2:16
3:54
Settings
4:58
You'll Almost Never Need to Change the Settings on Your Calculator
5:00
Tell Calculator In Settings Whether the Angles Are In Radians or Degrees
5:26
Graphing Mode
6:32
Error Messages
7:10
Don't Panic
7:11
Internet Search
7:32
So Many Things
8:14
More Powerful Than You Realize
8:18
Other Things Your Graphing Calculator Can Do
8:24
Playing Around
9:16
Graphing Functions, Window Settings, & Table of Values

10m 38s

Intro
0:00
Graphing Functions
0:18
Graphing Calculator Expects the Variable to Be x
0:28
Syntax
0:58
The Syntax We Choose Will Affect How the Function Graphs
1:00
Use Parentheses
1:26
The Viewing Window
2:00
One of the Most Important Ideas When Graphing Is To Think About The Viewing Window
2:01
For Example
2:30
The Viewing Window, cont.
2:36
Window Settings
3:24
Manually Choose Window Settings
4:20
x Min
4:40
x Max
4:42
y Min
4:44
y Max
4:46
Changing the x Scale or y Scale
5:08
Window Settings, cont.
5:44
Table of Values
7:38
Allows You to Quickly Churn Out Values for Various Inputs
7:42
For example
7:44
Changing the Independent Variable From 'Automatic' to 'Ask'
8:50
Finding Points of Interest

9m 45s

Intro
0:00
Points of Interest
0:06
Interesting Points on the Graph
0:11
Roots/Zeros (Zero)
0:18
Relative Minimums (Min)
0:26
Relative Maximums (Max)
0:32
Intersections (Intersection)
0:38
Finding Points of Interest - Process
1:48
Graph the Function
1:49
2:12
Choose Point of Interest Type
2:54
Identify Where Search Should Occur
3:04
Give a Guess
3:36
Get Result
4:06
5:10
Find Out What Input Value Causes a Certain Output
5:12
For Example
5:24
7:18
Derivative
7:22
Integral
7:30
But How Do You Show Work?
8:20
Parametric & Polar Graphs

7m 8s

Intro
0:00
Change Graph Type
0:08
Located in General 'Settings'
0:16
Graphing in Parametric
1:06
Set Up Both Horizontal Function and Vertical Function
1:08
For Example
2:04
Graphing in Polar
4:00
For Example
4:28

• ## Related Books

 1 answerLast reply by: Professor Selhorst-JonesMon Oct 20, 2014 11:32 AMPost by Saadman Elman on October 18, 2014[EDIT BY TEACHER: This student noticed a minor mistake in Example 1. Around 26:20, I say that a_3 = 8, but that is INCORRECT. It should actually be "-8". The negative sign is part of the number because of the minus sign. I'll try to get this fixed in the near future, but for now I'm just going to leave this note in case it confuses any other students.Thanks for pointing this out to me.]In example no. 1 a3 or a subscript 3 is -8 not positive 8. I would like this confirmed thanks. Your explanation was helpful! 1 answerLast reply by: Professor Selhorst-JonesSun Sep 7, 2014 10:50 AMPost by David Llewellyn on September 7, 2014Is a0 + a-1.x^-1 + a-2.x^-2 + a-3.x^-3 + ..... + a-n.x^-n considered a polynomial and would you consider it to be of degree -1 or -n or even zero as a0 could be written as a0.x^0 and x^0 would then be the largest, in the sense of furthest to the right on the number line, exponent of x? I suspect that it is a polynomial of degree -1 but I'd like this confirmed.

### Intro to Polynomials

• A polynomial is an expression of the form
 an ·xn + an−1 ·xn−1 + …+ a2 ·x2 + a1 ·x + a0,
where n is a nonnegative integer, an, an−1, ..., a0 are all real numbers (constants), and an ≠ 0.
• If the above definition is a little hard to understand, here are the key ideas:
• It starts from some nonnegative integer n. This number is the exponent that the very first x has: xn.
• It has this structure:   xn +  xn−1 + …+  x2 +  x +  , where each of the blanks is filled with a number. (That's what all those a's represent.)
• The a's (blank spaces above) can potentially be 0's, causing that spot to "disappear". The only spot that's not allowed to be 0 is an: the first spot. This means our xn is not allowed to disappear. (Otherwise why use n if we won't have xn?)
Putting all this together, we get expressions like x4 + 3x2 − 9x + 17.
• A polynomial function is a function that is made from a polynomial, like f(x) = x4 + 3x2 − 9x + 17.
• A polynomial equation is an equation made from a polynomial, like y = x4 + 3x2 − 9x + 17.
• While we will generally use x as the variable in polynomials, we should note that any variable can be used. Like in our work with functions, x is a commonly used variable, but there are others out there.
• The degree of a polynomial is the size of the largest exponent on a variable. If the polynomial isn't in order of largest to smallest exponents, the degree might not necessarily be the first exponent you see.
• Some types of polynomials come up often enough that they get special names. Sometimes the name is based on the degree of the polynomial:
• Cubic - Degree 3
• Linear - Degree 1
• Constant - Degree 0
Other times, the name is based on how many terms it has:
• Trinomial - 3 Terms
• Binomial - 2 Terms
• Monomial - 1 Term
• Polynomials can often be broken down into multiplicative factors by the distributive property (multiplication over parentheses). Occasionally we want to take two factors and multiply them together to expand the polynomial. In the most basic form of two binomials, we have the FOIL method:
 (a+b) (x+y) = ax + bx + ay + by.
This idea can work on larger factors or more than two as well: each term in a parenthetical group multiplies all the terms in the other parenthetical group.
• The reverse of expanding is called factoring, which we will explore extensively in later lessons.
• The long-term behavior of a polynomial is determined by the term with the largest exponent and whether or not that term has a positive or negative coefficient. This is called the Leading Coefficient Test. [To visually see what happens, check out the video for the various images. In general, though, you can imagine what ±x2 and ±x3 would do.]

### Intro to Polynomials

What is the degree of the below polynomial?
 5x3+12x2−5x+47
• The degree of a polynomial is the size of the largest exponent on a variable. Find the largest exponent on a variable, and the value of that exponent is the polynomial's degree.
• The term 5x3 contains the largest exponent, which is 3.
The degree of the polynomial is 3.
What is the degree of the below polynomial?
 −127a4+43a8−32a9+a
• The degree of a polynomial is the size of the largest exponent on a variable. Find the largest exponent on a variable, and the value of that exponent is the polynomial's degree.
• While the first term will usually have the largest exponent (on a variable), sometimes the polynomial is not in standard order. For this polynomial, the third term −32a9 contains the largest exponent, which is 9.
The degree of the polynomial is 9.
What is the degree of the below polynomial?
 973t2 +t4 − 107 t3 +1058
• The degree of a polynomial is the size of the largest exponent on a variable. Find the largest exponent on a variable, and the value of that exponent is the polynomial's degree.
• It's important to notice that the degree comes form the largest exponent on a variable. If the exponent is on a constant, it does not count.
• While the first term will usually have the largest exponent (on a variable), sometimes the polynomial is not in standard order. For this polynomial, the second term t4 contains the largest exponent (on a variable), which is 4.
The degree of the polynomial is 4.
What is the degree of the below polynomial?
 (x3−17)5
• The degree of a polynomial is the size of the largest exponent on a variable. Find the largest exponent on a variable, and the value of that exponent is the polynomial's degree.
• This problem could be solved by expanding (x3−17)5 out by hand. Write out
 (x3−17)(x3−17)(x3−17)(x3−17)(x3−17),
then simplify. HOWEVER! that would take a while, and there's a much faster and easier way to do it.
• Remember, the degree comes from the largest exponent on a variable. As we expand the above, the largest exponent on a variable will come come from whichever term is made by multiplying each of the x3's together. That term will be
 x3·x3·x3·x3·x3  =   x15
The degree of the polynomial is 15.
Give an example of a quadratic binomial.
• Quadratic means that the polynomial's degree is 2.
• Binomial means that there is a total of two terms.
• There are many ways this could be written, it just needs to have both of the above be true. The largest exponent on a variable must be 2, and that term can have any coefficient. There must be precisely one other term with a different exponent on the variable (or a constant instead of a variable).
[There are a wide variety of possible answers. They should be in one of the below forms:
 x2 +  x     or      x2 +
Some possible examples: x2 + x,   −5b2 + 50,   10ω2−32ω.]
Give an example of a cubic monomial.
• Cubic means that the polynomial's degree is 3.
• Monomial means that there is a total of one term.
• There are many ways this could be written, it just needs to have both of the above be true. There must be only one variable and it must have an exponent of 3. It can have any coefficient.
[There are a wide variety of possible answers. They should be in the below form:
 x3
Some possible examples: x3,   −4.7t3,   π·n3.]
Expand the below expression:
 (x+2)(x−6)
• To expand the two factors, we multiply them out through the distributive property. Each term in one parenthetical group multiplies all the terms in the other.
• (x+2)(x−6) = x ·x + x·(−6) + 2·x + 2·(−6)
• Simplify it once it has been expanded, then put it in order of largest exponents (on variables) down to the smallest, with the constant coming last.
x2 − 4x−12
Expand the below expression:
 (−3x+2)2 (x+5)
• First, rewrite the expression so that the parenthetical expressions do not have exponents on them:
 (−3x+2)(−3x+2)(x+5)
• At this point, we can expand either the left pair or the right pair first. Let's do the left. To expand the two factors, we multiply them out through the distributive property. Each term in the parenthetical group multiplies all the terms in the other.
 (−3x+2)(−3x+2)(x+5) = (9x2−12x+4)(x+5)
• Repeat the procedure of expanding, now using the newly expanded left parenthetical group and the parenthetical we did not use from last time. To expand, each term in the parenthetical group multiplies all the terms in the other.
 (9x2−12x+4)(x+5) = 9x3 + 45x2 − 12x2 −60x + 4x + 20
9x3 + 33x2 − 56x + 20
Expand the below expression:
 (t2 + 5t −8)(t3 −3t + 2)
• To expand the two factors, we multiply them out through the distributive property. Each term in one parenthetical group multiplies all the terms in the other.
• Be careful when simplifying: it can be easy to mix up what adds with what or to entirely forget a term when adding. It can help to check things off as you add them together on the line below. Use some sort of mark to remind you of what you have done and what you still need to do.
t5 + 5t4 −11 t3 −13 t2 + 34 t − 16
Describe the left-hand and right-hand behaviors of the below equation:
 y = −3x5 + 42x3−180x2 + 539
• Notice that the equation is a polynomial. Thus, it's a question of how the polynomial behaves as it goes very far to the left (x→ − ∞) and very far to the right (x → ∞).
• We know how it will behave by the Leading Coefficient Test. Just look at the degree of the polynomial and the sign (+ or −) belonging to the coefficient of that largest exponent variable.
• The term with largest exponent on a variable is −3x5. Thus the polynomial has a degree of 5, which is odd, and is negative. Use this information to apply the Leading Coefficient Test.
The left-hand side goes up and the right-hand side goes down.

*These practice questions are only helpful when you work on them offline on a piece of paper and then use the solution steps function to check your answer.

### Intro to Polynomials

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

• Intro 0:00
• Introduction 0:04
• Definition of a Polynomial 1:04
• Starting Integer
• Structure of a Polynomial
• The a Constants
• Polynomial Function
• Polynomial Equation
• Polynomials with Different Variables
• Degree 6:23
• Informal Definition
• Find the Largest Exponent Variable
• Quick Examples
• Special Names for Polynomials 8:59
• Based on the Degree
• Based on the Number of Terms
• Distributive Property (aka 'FOIL') 11:37
• Basic Distributive Property
• Distributing Two Binomials
• Longer Parentheses
• Reverse: Factoring
• Long-Term Behavior of Polynomials 17:48
• Examples
• Controlling Term--Term with the Largest Exponent
• Positive and Negative Coefficients on the Controlling Term
• Even Degree, Positive Coefficient
• Even Degree, Negative Coefficient
• Odd Degree, Positive Coefficient
• Odd Degree, Negative Coefficient
• Example 1 25:11
• Example 2 27:16
• Example 3 31:16
• Example 4 34:41

### Transcription: Intro to Polynomials

Hi--welcome back to Educator.com.0000

Today, we are going to have an introduction to polynomials.0002

By this point, you have seen polynomials, even if you don't remember the name, countless times in previous courses.0005

As a brief reminder, they are the ones that look like x2 - 2x + 9,0010

or maybe 3x5 - 8x3 + 10x2 + x + 47.0014

This stuff looks familiar; now, you might wonder why you have spent so much time on them before,0019

and why we are studying them yet again in another course.0024

In short, it is because polynomials are ridiculously, absurdly useful.0028

They come up in every branch of science, from physics to medicine to economics.0033

They are going to be important if you are going to do engineering work; they are going to be important if you are going to do computer programming work.0038

They are going to be important for pretty much anything you want to do.0043

If you want to study higher-level mathematics, they are going to be important in that, too.0045

Polynomials are very important; they are going to be important in any branch of science, and in anything that is in higher, deeper levels of mathematics.0048

So, that is why they keep drilling them for all these years--because you really have to understand polynomials0056

for a huge number of things, so it is really important to get a good grasp on it now.0061

A polynomial: what is a polynomial? Formally, we define it as an expression of the form0066

anxn + an - 1xn - 1 +...+ a2 times x2 + a1x + a0.0071

And now, don't worry; these little things down here we just call the subscripts, which just means to say that there is a,0082

but then there are many different a's; there is an, an - 1, an - 2, and so on and so on...0089

a2, a1, a0...just many different a's.0096

What this expression means: we have that n is a non-negative integer, and all of our a's0100

(the an, an - 1, and so on, up until a0), are all real numbers,0106

which is to say that they are just constants; and finally, an itself, the first one,0110

the one at the very front, is not equal to 0.0115

Now, that might seem a little complex in its formal definition; but don't worry;0119

we are about to explain what is going on, so we can really understand what a polynomial is.0122

So, our expression, once again, was anxn + an - 1xn - 1,0126

and so on and so on...a1x + a0.0131

The first thing that we want to get to is: we want to start with this non-negative integer, n.0135

This n is really important; that n can be any number...something like 1 or 5 or 968.0140

It is just the exponent that the very first x has; so we could have x10147

(which we would normally write as just x), and then other stuff after it.0152

Or we could have x5, and then other stuff after it; or we could have x968, and then other stuff after it.0155

The n is basically our starting point--what is our starting exponent going to be?0165

Then, we have this structure: _xn + _xn - 1 + _xn - 2...so on and so on,0170

until finally we get _x2 + _x + _.0179

If we took x5, then we would have _x5 + _x4 + _x3 + _x2 + _x + _.0184

We just fill in those blanks with numbers.0197

That is what all of these a's represent; these are our blanks, down below.0200

They are the things that we are filling in; the a's represent those blanks.0207

They are just a number that is going to get stuffed into that place.0210

And finally, the a's (blank spaces) above can be, potentially, zeroes; so if we had a 0 here, we would just knock out the whole thing.0215

And we would pretend it wasn't there; we would read it as xn +...and then xn - 2 would be next.0223

If we have _x2 + _x + _, and we have 5x2 + 0x + 3,0228

we would probably just read this as 5x2 + 3.0238

So, if we have an a as a 0, it can cause that spot to just disappear.0241

Now, the only spot that is not allowed to disappear is an: an, the first spot, this one up here, is not allowed to be 0.0247

Why not? Because, if it was 0, then our xn would just disappear.0259

If we were able to have 0, then it would be gone; and so, if it is gone, our xn would disappear,0263

at which point, why did we choose n in the first place, if we are not even going to have xn show up?0269

So, since we want to use n (that is why we chose n), we can't have our very first spot disappear and get rid of that n.0274

And that is it--that is a polynomial: _x to the exponent, plus _x to the other exponent, plus blank...and so on and so forth.0280

That is pretty much just the structure of a polynomial.0287

If you can remember that, that is the important part.0289

While a polynomial is technically just an expression, like, for example, x4 + 3x2 - 9x + 17--0292

a polynomial is just this expression of _x to the exponent + _x to the exponent + _x to the exponent--0299

that is all it is--just that structure of _x to the exponent--we normally use them to make functions or equations.0306

So, a polynomial function is just a function that has been made out of a polynomial.0314

A polynomial function is a function that is equal to some polynomial.0317

And a polynomial equation is just an equation made out of it, as well.0322

So, we could have y = polynomial, or we could have function = polynomial.0328

That is it; also, while we will generally use x as the variable in polynomials, we should note that any variable can be used.0333

Any variable can be used; the important thing is that we are just following this _something to the exponent structure.0341

Like in our work with functions, we normally use f(x); but there is no reason that we have to use x.0346

x is a commonly-used variable, but it is not the only one out there.0352

There are others out there; so all of the below are just as valid as x4 + 3x2 - 9x + 17.0356

We could have z4 + 3z2 - 9z + 17--0363

representing the same thing; but instead, now we have a different variable being the placeholder.0368

Or we could have l to the fourth and more things, or θ to the fourth.0372

Any symbol can be our placeholder; we just want something that is being that placeholder, and being raised to an exponent.0376

The degree of the polynomial is the value of n in this expression; it is whatever our highest exponent is at the front.0385

Informally, we just want to see it as...the degree of the largest exponent on a variable.0391

So, that is what we want to think of degree as: the largest exponent on one of our variables.0399

If the polynomial isn't in order of largest to smallest exponents...0404

Normally we are in order--we go to n, and then next we are at n - 1, and then next we would be at xn - 2, and so on0407

and so on and so on, until eventually we got to x2, and then x1, and then...0415

although you might not remember this from exponent work before, x0, which we will talk about0423

in exponents later on--but the point is that we keep lowering the exponent--0428

we keep going and going and going, until we are finally at a constant.0431

But if our polynomial isn't in order of largest to smallest exponents, the degree might not necessarily be the very first one that you see.0435

It might not necessarily be the one at the very beginning; it could be somewhere in the middle,0442

if we aren't necessarily in that order of largest to smallest exponents.0446

The important thing is just to find the largest exponent on a variable; and that is your degree.0450

Let's see some examples: we could have a polynomial x2 + 2x + 1.0455

We look at this one, and we say, "Oh, the largest exponent on anything is that 2"; so we get a degree of 2.0460

We look at this one, 5x + 3; and the biggest one here is just this x.0468

What is its exponent? The exponent of anything is just to the 1, if it doesn't have something already, so we get 1.0471

We look at the next one: 7x3 - 4x47 + 8.0479

The one at the front is x3, but it isn't going to be our degree.0483

The degree ends up being...this one isn't in our usual order; it isn't in that general form0487

of xn and then xn - 1 and then xn - 2; this one is out of order.0492

But that doesn't mean that we can't find its degree; we just look through.0497

We look at all of our x's, and we end up seeing that 47 is the largest exponent on any of our variables.0501

And so, it is 47 that is our degree.0507

Finally, the last one might be a little bit confusing, as well.0509

We see this one, and we think, "Oh, x3...wait, there is an even larger exponent here."0512

We have 35, but 3 is not an x; it is not a variable.0516

So, since it is not a variable, it is out of the running, which leaves us with x3 as what we have.0524

And so, the degree of that is 3; so you are looking for a variable (make sure it is a variable) with the highest, largest exponent.0530

And that is your degree for a polynomial.0537

Since a lot of different polynomials come up very often, we have some special names for them.0541

Some types of polynomials get special names, and so we want to know them.0545

They are not super important to remember, although quadratic will come up so often, it is definitely going to be burned into your memory.0548

It is not super important to absolutely remember these; but they will come up.0555

And so, you want to know them, because you might have to know these vocabulary words.0558

You can figure out what name to use, based on the degree of a polynomial, for these ones.0562

A cubic is a degree 3 polynomial; this one has a degree of 3 here; or 5x3 - 3x2 + 27, once again, has a degree of 3.0566

A quadratic has a degree of 2; so it is x2 + x + 1 or -17x2 + 20x - √2.0577

A linear has a degree of 1: x1, πx1...0585

And then finally, a constant is just a degree 0 polynomial, which is to say it has no variables in it at all.0592

So, 1 has no variables; 5,111,723 still has no variable--there is no x here, so since there is no x, we have degree 0.0599

We can also talk about a polynomial based on the number of terms that make it up.0613

Once again, it is not super important to have this really memorized; but you want to be familiar with0616

and aware of these vocabulary terms, because they will show up now and then.0620

A trinomial is something that has three terms; we can remember this from trinomial,0624

like a tricycle or a triangle--they are all things having to do with the number 3.0628

x2 + x + 1: the squared isn't so much the important part as the x2; we have three things.0633

47x9 + x3 + 2: the degree no longer matters.0642

It is not about the degree, so I really should not have accidentally circled that 2...x2...0648

It is just the number of things we have: 47x9 + x3 + 2...0657

A binomial is something that has two terms; x and then 1, or -52x7 and 892x.0661

It doesn't matter that it is a coefficient times an x; that is OK.0671

It is allowed to be a coefficient times some variable raised to some exponent.0674

But that is the whole thing--that is one of our terms for this.0678

A binomial has two terms; it could be x + 1 (as simple as that), or it could be more complex, like -52x7 + 892x.0681

Or we could have one term, which is x, or maybe even something really, really large, like x raised to the 1,845.0689

All right, the distributive property: very often, we are going to need to either factor polynomials--0697

break them into their multiplicative pieces--or expand these factors into a polynomial that is in general form.0702

So, take these multiplicative pieces, and then combine them together to get something larger0708

that gives us the whole polynomial in that general form that we saw of _x to the exponent + _x to the exponent.0713

We will see why this matters later on, especially in our next lesson, where we will talk about roots and zeroes of polynomials.0720

But for now, it is really important to understand how we get somewhere from (x + 1)(x + 2) into x2 + 3x + 2.0727

This is probably going to be a bit of a review for most of you; but it is good to understand why this is happening,0734

as opposed to just being able to do it mechanically.0738

So, let's look at what is making it up.0740

The thing this comes from is the distributive property, which says how multiplication interacts with parentheses.0742

If something multiplies against parentheses, it distributes to every term that is separated by addition or separated by subtraction.0750

For example, if we have a(b + c), then the a gets distributed onto the b, and the a gets distributed onto the c.0756

So, we get ab + ac; that is how distribution works.0765

How is that connecting to FOIL-ing things--how is it connected to different multiplicative factors for polynomials?0770

Well, our distributive property is a(b + c) becomes ab + ac.0776

From this property, we can use that on two different things in parentheses.0781

We can distribute parentheses onto other parentheses; and the most basic form with two binomials,0786

which is to say two things with two terms--we have the FOIL method.0791

For example, if we have (a + b)(x + y), we can think of (a + b) as just being a block.0795

So, like a is a block in our top example up here, we can think of (a + b) as being a block down here.0802

(a + b) goes onto x, and (a + b) goes onto y; so we get (a + b) times x and (a + b) times y.0810

Then, we turn right around, and we distribute in the other direction.0817

We take x, and we distribute that onto the a and onto the b; and we take y, and we distribute that onto the a, and distribute that onto the b.0820

And so, we get ax + bx, and then ay + by.0827

Now, what does FOIL mean? FOIL is a mnemonic to help us remember the order of multiplication: Firsts, Outers, Inners, Lasts.0831

Let's see how that comes to be; that end would be this way, where it is (a + b)(x + y).0840

We would do the firsts; we would do a and x (those are the first things); so we would get ax.0847

And then next, we would do the outers; a is on the outside, and y is on the outside (the outer part of our parentheses); we get ay + ay.0854

b times x would be our inners, the things on the inner part of the parentheses...b times x.0865

And then, b times y would be our lasts, because they are the last thing in each of our parentheses; plus b times y.0872

And we see that these two things are exactly the same thing; it is just reordered.0879

So, the distributive property and FOIL have the same thing going on here.0884

It is just a way of being able to say, "How is this going to multiply? How is it going to distribute onto the other thing?"0888

The way that we are making this FOIL method is two distributions, one after another.0893

But when we are actually using the distributive property to multiply out polynomial factors,0897

we probably want to think in terms of this first term, times the other terms inside,0901

and then the second terms times the other terms inside, and then the third term, and so on, and so forth, and so on.0906

This idea can expand into working on much longer parentheses than just two terms inside of it.0913

So, instead of just using binomials, we could have something like (x2 + 2x + 2)(3x2 - x).0919

So now, our first one has three terms, as opposed to just two.0925

But the same method still works: we can have x2 times 3x2, and then x2 times -x.0928

Next, we will do 2x times 3x2, and then 2x times -x.0941

And then finally, we will do 2 times 3x2, and 2 times -x; great.0952

Each term in the parenthetical group multiplies all of the terms in the other parenthetical group.0964

We have x2 multiplying against 3x2, and then multiplying against -x.0969

So, each term in the parenthetical group--one of the things in our parentheses--multiplies all of the terms in the other parenthetical group.0975

We start with factors, and we multiply them out; when we do that, it is called expanding.0982

What we just saw here is called expanding.0986

When expanding, we are normally expected to simplify.0989

I didn't simplify this one, because we don't really want to get into having to do that right now.0992

But we could simplify it pretty easily at this point.0997

We would multiply things out; we would get x2 times 3x2 (becomes 3x4).0999

And then, we would do that with all of the other ones, and eventually we could add like terms together.1004

And we could simplify this into one of our general-form polynomials of _x to the exponent + _x to the exponent + _x to the exponent.1008

We can get it back into that general form.1016

Expanding is also sometimes called FOIL-ing; now, this is technically incorrect for larger factors,1019

because remember: FOIL is based off of that mnemonic: Firsts, Outers, Inners, Lasts.1024

So, that requires it to be 2 and 2 (two binomials put together).1028

But when people say this, we still know what they mean; FOIL-ing just means...it is another way of saying "expanding."1032

So, when somebody says "FOIL these polynomials" or "expand these polynomials," they are really getting across the same idea.1039

Use the distributive property; simplify it.1044

The reverse process, taking a polynomial and breaking it up into those multiplicative factors, is called factoring.1047

So, when we have this large, general-form polynomial, and we break it into those pieces,1053

like (x2 + 2x + 2) and then (3x2 - x), that is breaking it into the multiplicative factors; so we call it factoring.1058

The long-term behavior of a polynomial is determined by the term that has the largest exponent.1068

Other terms can have an effect; but their effect will become less and less noticeable as x approaches either positive or negative infinity.1073

Basically, as x goes very far in either direction (either to the right or to the left),1080

it is going to end up being the case that the polynomial will be controlled1085

by whichever exponent is largest--the term that has the largest exponent.1088

Why is this the case? Well, let's consider: if we have x, x2, x3, x4, and x5,1092

and we plug in different values for x, when we plug in 1, they end up pretty much all being the same.1098

1, 1, 1, 1, 1...they are all exactly the same.1103

We get nothing but the same thing out of each of them.1106

But if we plug in something different, like 2, we start to see differences come up: 2, 4, 8, 16, 32.1108

Of course, the differences aren't very large yet; but as the numbers get larger and larger that we are plugging in,1114

5, 25, 125, 625, 3125...the difference between x2 and x5 is now 3100.1121

And if we just get up to x as 10 (plug in 10 for x), we get 10, 100, 1000, 10000, 100000...1133

massive differences between x5 and x2, or x5 and x.1143

Even the difference between x4 and x5 is a difference of 90,000.1147

And we are only at x = 10; clearly, x5...if we place all of these side-by-side...is going to be the massive winner.1155

It is going to have huge amounts of control; it is going to contribute so much more to what the value will end up being1162

than either x, x2, x3, or x4.1167

None of those are going to be nearly as important as x5.1170

So, as x becomes very big (positive or negative), the polynomial will be controlled by whichever term has the largest exponent.1173

The term that has the largest exponent--in this case, when we compared these 5, it would be x5.1180

Whatever has the largest exponent is going to end up taking over.1187

Even if it has a really, really tiny coefficient in front, like 0.0001 times x5, that will eventually get cracked.1190

As x5 becomes larger and larger and larger, and we plug in fairly large x, like, say, 10000,1198

it will be able to knock out that coefficient and still be more important than x4, x3, x2, x.1205

So, the only thing that really matters is which one has the largest exponent.1210

Once you can figure out that, you know which one is going to be in control of the function at the extreme values of ±∞.1214

One other thing can have an effect, though.1222

The leading coefficient is very important, because it is going to be able to flip it.1224

So, the largest exponent is the term that determines things; the term with the largest exponent determines what will happen.1229

But the coefficient on that term will also matter.1236

If the coefficient is positive, it behaves normally; but if the coefficient is negative, it is going to flip the term.1239

What do I mean by that? Well, let's look at x2.1245

x2 has a normal parabola arc like that; but if we have -x2, it is going to flip it.1248

So, with x2, we end up going up on the left and up on the right.1256

But with -x2, we end up going down on the right and down on the left.1259

So, it is going to be down on both sides, because the negative is flipping it.1264

This leading term, whether it is a plus or a minus in front, is going to have control over what happens.1268

Either we are doing things the normal way, or we are going to flip to the opposite of that.1276

So, when a polynomial is in standard form (which is to say that the largest exponent is in the front), we call this the leading coefficient test.1281

By knowing what the leading coefficient is and the degree of the polynomial, we will be able to know what the long-term behavior is.1288

All you need to know to use the leading coefficient test is the degree of the polynomial and the sign of the leading coefficient,1294

which is going to be either plus or minus (or negative, technically).1302

We know what its long-term behavior will be like; we will see some pictures on the next one.1307

Long-term behavior--what do we mean by that? That is what happens as x gets very big--1310

as x goes out to plus or minus infinity, as it gets very, very far away.1315

We haven't really determined what it means by very, very far away; but it is just eventually, in the long run, how things will behave.1320

Let's look at some pictures to understand what this means.1328

So, for the leading coefficient test, if we have an even degree (which is a polynomial1330

where the leading exponent is going to be even, like x2, x4, x6, x8, etc.),1335

then if the coefficient is positive, on the right and on the left, we are going to be going up,1345

because, when we plug in a very large positive number, it is going to still stay a very large positive number.1351

If we plug in a very large negative number, then that even exponent will flip it to being positive; so we will still be going up.1357

On the other hand, if we have a coefficient that is negative, then when we plug in a very large one,1364

we will get a very large number out; but it will then get flipped to going negative.1369

If we plug in a very large negative number, then it will get flipped to positive.1372

But once again, the negative coefficient will hit it; and so it will go down.1376

So, for an even degree with a positive coefficient, both the left and the right side go up.1379

If we are an even degree with a negative coefficient, both the right and the left side go down.1383

An odd one, though (that is to say, something like x1, x3, x5, x7,1389

and so on and so on)...if the coefficient is positive, then as we go very far to the right,1396

we are going to go up; we plug in a very large number, and we will get a very large positive number out of it.1402

But if we plug in a very large negative number, it has an odd exponent; so x3...1407

-2 plugged into x3 is -2 times -2 times -2; three negative signs means we are left with a negative sign; so we would get -8.1415

So, it starts to go down as it goes negative and negative.1422

On the other hand, if we had a negative coefficient, then we would end up flipping that.1426

As we plug in very large positive numbers, they will get flipped down to going in the negative way.1432

And if we plug in a very large negative number, it will come out negative;1437

but then it will get flipped by that coefficient, and it will go positive; it will go up; great.1440

So, the leading coefficient test is: if we know it is an even and a positive, it is going to be up on both sides.1445

If it is an even, and it is a negative in front, then it is going to be down on both sides.1450

Odd and positive is going to be down on the left, up on the right.1453

And odd with a negative is going to be down on the right, up on the left.1458

So, just keep those pictures in mind, and think of flipping.1464

Now, notice that in the middle, we have these dashed lines; and what those dashed lines say1467

is that we don't have any idea what the middle part is going to look like.1472

The leading coefficient test only tells us what happens on the extremes--on the far left and the far right.1475

What is going to happen eventually, one day, in the long term?1484

But what happens in the middle--that is going to depend on the specific thing.1488

It could be very interesting; it could be not that interesting; we don't know what it is going to be until we get at specific function that we are looking at.1490

Then, we can figure out what it is going to be exactly.1501

The leading coefficient test just tells us what is going to happen in the long term, to the very far right and the very far left--those portions.1503

All right, we are ready for some examples.1513

What is n, the degree, for 2x4 - 8x3 + 25x - 19?1514

Remember, the degree is the largest exponent on a variable.1522

We go through; we look at all of our variables; and we see that this is the largest exponent on any of our variables.1532

We might notice this 25; but then we remember that it has to be a variable.1539

So, the 25 doesn't get considered; and so, x4 is the case.1544

n is just our degree for a polynomial; so we have n = 4; and what is an?1549

Remember, the first one was an here; and then a3 goes with the x3.1555

And then, a2 would go with x2; but where is that?1561

First, an is 2, which is also the exact same thing as a4, because we have n as 4, so a4 = 2.1565

What is a3? Well, what is the coefficient for x3? That is 8.1578

What is the coefficient for the x2? We look at this, and we realize that that didn't show up at all.1585

But we could rewrite this as 2x4 - 8x3 + 0x2,1591

because x2 never showed up, so it must have been taken out by something; it has been taken out by this 0.1598

Plus 25x, minus 19...so if that is the case, then it must be that it is a2 = 0.1603

The plugging in for a2 must be 0, because it has to be able to take out that x2 term.1615

Then, from there, we just continue: a1 is equal to 25;1621

and finally, our last one is a0 at the very end; a0 equals -19.1625

So now we see what all of the coefficients are; we know what the degree is; great.1633

The second example: Expand and simplify this expression; we have (x - 2)2(x3 - x + 3).1637

The first thing we have to do is realize that (x - 2)2 is just the same thing as (x - 2)(x - 2).1644

If I have smiley face squared, then that is the same thing as smiley face times smiley face.1651

If I have (x - 2)2, then that is just (x - 2)(x - 2).1657

Then, x3 - x + 3: let's start on the left and work our way to the right.1661

(x - 2)(x - 2); well, that will get us x2 (x times x) - 2x - 2x -2(-2) (becomes + 4).1667

And then, x3 - x + 3...I haven't really worked with that yet.1684

Let's simplify the left side first: x - 2x - 2x + 4...sorry, not x times x; x times x becomes x2; sorry about that.1688

We have x2 - 2x - 2x + 4; x2 - 2x - 2x becomes x2 - 4x, as we combine like terms; + 4.1698

Then, times the quantity x3 - x + 3.1707

All right, let's use different colors for the various pieces we have here.1712

x2 times x3 becomes x5; x2 times -x becomes -x3;1715

x2 times positive 3 becomes + 3x2.1724

The next color is for -4x; that was our x2 portion.1728

-4x we will do in blue; so -4x times x3 will become -4x4.1733

-4x times -x becomes positive 4x2; and then, -4x times positive 3 becomes -12x.1741

The final one we will do in green; 4 times x3 becomes + 4x3;1751

4 times -x becomes -4x; 4 times 3 becomes + 12.1757

Great; now we have to simplify this.1763

Now, this isn't too difficult to simplify, but it is easy to get lost.1765

Each of the steps that we are about to do is pretty easy; the hard part is making sure we don't accidentally have any tiny missteps as we work through this.1769

So, I would recommend checking and doing them by exponent.1777

The first thing we will do is look at all the x5's.1780

We see that there are no other x5's, so we just bring it down; we have x5,1783

and then we will cross this out, so that we don't accidentally see it again, and don't accidentally end up trying to use it again.1787

Next, we have x4's; where are our x4's? We have -4x4.1792

Do we have any other x4's? We look through it; no, we don't have any other x4's.1796

So, we bring that down; -4x4; and then we cross it out, so we don't accidentally try to use it again.1801

Next, let's look for our x cubeds; we have an x cubed right here--anywhere else?--yes, we do; we have another x cubed here.1807

So, we bring those together: -x3 + 4x3 becomes + 3x3.1812

-1 + 4...we get + 3x3; and then we cross those out.1819

Next are 3x2 and 4x2; there are no other x squareds; 3x2 + 4x2 becomes 7x2.1825

We cross those out; next are x's; -12x - 4x; combine those together, and we get -16x.1833

Take those out; and + 12; there we are.1841

Now, you don't have to do this method of saying, "Here are my x5's; here are my x4's" and so on,1846

and so on, and then crossing them out as you go.1852

But this is a great way to make sure you don't accidentally make a mistake.1854

It is easy, when you are working with this many terms and trying to put them together and simplify,1856

to make one tiny mistake and lost the entire problem because of it.1861

So, it is a good idea to have some method of being able to follow your work and make sure1864

you don't accidentally try to do the same thing twice, or completely miss a term.1867

All right, the next one: Give an example of a quadratic trinomial, a cubic monomial, and a linear binomial.1871

Quadratic trinomial: remember, quadratic meant degree 2; and then, trinomial meant three terms.1879

A cubic monomial is a degree 3 (cubic means degree 3); monomial...mono- means single, like monorail,1890

a train track with one rail (not really a train anymore); a monomial is one term.1900

And then finally, linear is degree one; and binomial is two terms (bi- like bicycle); great.1907

So, if we want to give an example of this, we just need something that is degree 2 and 3 terms.1919

If it is degree 2 and it has 3 terms, then we are going to have something that has x2 at the front;1927

and it has to have blank spots for a total of three things.1932

Now, we can't have zeroes show up in these, because then it would disappear and we wouldn't have a term there.1938

We will have to put in something; so let's call it 5x2 + 3x, and we will make it -17.1942

You could plug anything into these blanks, and the answer would still be correct.1949

5x2 + 3x - 17; there is our quadratic trinomial.1952

Next, we do a cubic monomial; we know it has to be degree 3.1958

Degree 3 means it has to be x3; and it is only one term, so there is going to be a blank in front of the x3.1963

But we are not allowed to have any other blank things, because if we did, then we would have more than one term.1969

We are only allowed to have one term; so all of that gets taken right out--it disappears.1977

We have just _x3; we plug whatever we feel like in...I feel like -47, so we get -47x3.1982

Great; the final one--we have a linear binomial: a binomial has to have two terms, and linear is degree 1.1990

So, we have x1, with some blank in front of it, plus blank, _x + _.1998

What goes in those blanks? Whatever we feel like.2004

We are not allowed to have any other blanks, though, because then we would have more than two terms.2006

Also, we can't have any more blanks, because we are linear, and that is the most that we have there.2009

So, _x + _...let's put in 1 for the x and -7 for the constant; so we have x - 7.2013

Great; the last thing--explain why it is impossible to have a linear trinomial.2022

So, if you are going to have a linear trinomial, let's see what that structure has to be.2027

Well, if we are linear, we know that x is going to be at the front.2032

And so, if we do the normal structure that we have for polynomials, it will be _x + _.2036

But if it is a trinomial, "trinomial" means we have to have three terms.2041

So, if we try to force on a third term, we would have to have _x2.2046

We already have _x + _, so the only way to go is to go to the left; we have to have higher and higher exponents.2051

So, _x2...all of a sudden, now we are a trinomial, but we are not linear anymore.2058

So, it means that we can't have both of these things at the same time.2065

We can't both be linear and have a third term; otherwise we would have to have x2,2068

at which point we wouldn't be linear anymore; we would be quadratic.2073

So, it is going to be one or the other; you can't be both a trinomial and a linear function.2076

The final example: What is the degree of y = (-2x2 + 4)407?2082

Now, you see this at first, and you might get scared, because you think, "I can't possibly expand 407 times--I can't do that!"2088

But don't worry; all they asked for was the degree.2094

So notice: if I have (x2 + 3)(x5 + 48), do I have to look at anything else2097

to figure out what the degree is going to be, other than the front parts?2107

No, because I know only the x2 and the x5 are going to come together to make x7.2110

And there is going to be other stuff; but I know I can't get any higher exponents out of this than the x7.2114

It is going to be the leading term that will have the highest exponent.2120

It is going to be the exact same thing on this one.2123

It is going to be that -2x2; it is a question of how many times -2x2 hits -2x2.2126

That is the only thing that is going to be able to really bring increases of the degree.2132

There is going to be a whole bunch of other stuff; but we are not concerned with it, because all that they asked for was the degree.2136

It is going to be -2x2 raised to the 407, plus other stuff.2141

But we don't care about the other stuff: -2x2 to the 407...we distribute that...-2407(x2)407.2148

So, if we have 407 x2, then it is x2 times x2 times x2 times x2...2160

So, it is going to be the same thing as x2(407), because they are going to iterate that many times; it is going to hit that many times.2165

So, we have (-2)407, times x2(407); (-2)407x814.2174

So, our degree is n = 814; that is our degree for this polynomial.2190

Now, as x goes very far to the left (x goes to -∞), will y go up or down (y approaches +∞ or y approaches -∞)?2198

And then, what about as x goes very far to the right--as x goes to positive infinity?2206

So, to do that, we need the leading coefficient test.2209

At this point, we already know what the degree of this polynomial is.2214

This polynomial is n = 814; so it is an even-degree polynomial.2219

Now, we want to figure out what our leading coefficient is; is it positive or negative--plus or minus?2226

We do that: -2 to the 407, times x to the 814...well, if it is a negative raised to an even number, they will all get canceled out.2233

If it is a negative raised to an odd number, one of them remains, because it will end up getting to stay around.2243

All of the even part will get canceled out, but that odd is an extra +1, so it stays around.2250

So, we will get -2407x814; that means we have a negative sign right here.2255

So, by the leading coefficient test, we have negative and even; negative and even means an even one.2265

Even normally goes in the same way that a parabola goes; it cups up, normally (even at positive).2276

But even at negative will flip that cupping shape, and we will get that.2283

Now of course, we don't actually know what is in the middle; all we know is the extremes,2287

because that is all we were guaranteed from the leading coefficient test.2292

But that is all we have to figure out, because it is as x approaches negative infinity.2295

So, from this, we see, even as it goes negative, that we go down on the left and down on the right.2298

So, as x approaches negative infinity--as x goes very far to the left--we are going to approach y going to negative infinity.2304

As x goes very far to the right (x goes to infinity), we are going to get y going to negative infinity, once again.2312

All right, great--the leading coefficient test should be able to figure that out.2321

All right, we will see you at Educator.com later.2324

Next time, we will look at roots and zeroes of polynomials and get a really good understanding of how these things are working.2326

All right--goodbye!2331