Question

How do you find the general solution for cos2A=cos^2A

Answer 1

Answer:

A =  0 +/- nπ radians ,  where n is an integer.

Step-by-step explanation:

cos 2A =  cos^2 A

Use the identity cos 2A = 2 cos^2 A -1  :

2cos^2 A - 1 = cos^2 A

cos^2 A = 1

Cos A = +/-1

When cos A = 1,  A = 0 +/- 2nπ radians.

when cos A = -1, A = π +/- nπ radians.