SOLUTION: Verify the identity. cos 4u = cos^2 2u - sin^2 2u

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Question 1106776: Verify the identity.
cos 4u = cos^2 2u - sin^2 2u
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Verify the identity.
cos 4u = cos^2 2u - sin^2 2u
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Sub x for 2u
cos(2x) = cos^2(x) - sin^(x)
QED