In this lesson we are going to talk about the Law of Cosines. Using Law of Cosines is very similar to when we used Law of Sines. We are using both of those for non-right triangles; it is very important to remember that there are different things that you can use for right triangles, and then there are things that you can use for non-right triangles. The Law of Cosines consists of three different formulas, depending on what you need - what measure you have to find. You'll learn how all these formulas have the same pattern, which will help you remember them easily.
*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.
Law of Cosines
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.