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

User Gaye
by
6.1k points

1 Answer

5 votes

Answer:

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

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.

User Seefa
by
6.4k points
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