SOLUTION: Simplify the expression by using a double-angle formula. 2cos^2 4theta -1 Thank you!!

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Question 1085306: Simplify the expression by using a double-angle formula.
2cos^2 4theta -1
Thank you!!
Answer by ikleyn(52847) About Me  (Show Source):
You can put this solution on YOUR website!
.
Double angle formula for cosines is  cos%5E2%282a%29 = 2%2Acos%5E2%28a%29-1.


Use it, and you will get


2cos%5E2%284theta%29+-1 = cos%5E2%288theta%29.

Solved.