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Geometric Mean

You are probably familiar with the arithmetic mean, also known as the average, which is the sum of n...

Area of a Regular Polygon

Polygons are two-dimensional shapes, made of straight lines that connect up and form a closed figure. If a polygon...

Surface Area of a Cylinder

To find the total surface area of a cylinder, we need to find the areas of its three surfaces:...


SohCahToa is an acronym which helps you remember how to find the basic trig functions: sine, cosine and tangent....

Law of Sines: How to Use & Practice Examples

The Law of Sines (or the Sine Rule) tells us that the ratio of a side length to the...

Law of Cosines: How to Use & Practice Examples

We have already seen how to solve triangles using the Law of Sines. Such problems involve two sides and...

Triangle Inequality

The Triangle Inequality Theorem states that the sum of the lengths of any two sides of a triangle must...

Surface Area and Volume of a Sphere

The surface area of a sphere is the number of square units that will exactly cover its surface. The...