Algebra-2

In , where is a right angle and , we can calculate the side lengths of the triangle and then evaluate .

 

Let's label the sides of the triangle as follows:

Side is the hypotenuse.

Side is opposite to .

Side is adjacent to .

 

Using the definition of cosine, which is adjacent/hypotenuse, we can determine that .

 

Let's assume that the length of is , and the length of is (where is a positive constant).

 

Using the Pythagorean theorem, we have: