(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

prove: cos^2(x)= (1+cos2x)/(2)

2. Relevant equations

i broke the cos^2(x) down to 1-sin^2(x)???

3. The attempt at a solution

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# Homework Help: Proving identities

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