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

(3/5)cos^{2}x + (3/5)sin^{2}x

3. The attempt at a solution

I would think the answer would be 6/5, but it looks like the book is saying 3/5. I had a similar problem to this the other day and I tried finding it in my history but I couldn't.

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# Trig identities

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