(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] Trig Identity

1. The problem statement, all variables and given/known data

cos^4 (x) = (3/8) + (1/2)(cos(2x)) + (1/8)(cos(4x))

2. Relevant equations

cos2x = 2cos^2 x - 1

cos^2 x = 1 - sin^2 x

3. The attempt at a solution

Can someone please give me hints? Thanks.

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# Homework Help: Trig Identity RHS LHS problem

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