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

1. (sinx - cosx)(sinx + cosx) = 2sin^2x-1

2. (2sinx + 3cos)^2 + (3sinx - 2cosx)^2 = 13

2. Relevant equations

N/A

3. The attempt at a solution

For 1. L.S. = sinx^2+sinxcosx-sinxcosx-cosx^2, the sinxcosx cancels and I'm lost.

I haven't a clue how to do the second one.

I missed a couple of day of school because of the flu before christmas break, so I need to understand this. Some please help.

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# Homework Help: Trig Identity homework

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