SOLUTION: verify identity cos^2x-2sin^2x=3cos^2x-2

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Question 441181: verify identity
cos^2x-2sin^2x=3cos^2x-2
Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
We simplify the left side of the identity:
=%28cosx%29%5E2-2%281-%28cosx%29%5E2%29=%28cosx%29%5E2-2%2B2%28cosx%29%5E2=3%28cosx%29%5E2-2 as you see we get
the same expression as the right side, thus the identity is true.