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

Prove the following product-to-sum identities:

i) cosucosv= 1/2[cos(u + v)+cos(u - v)]

ii) sinusinv= 1/2[cos(u - v) - cos(u + v)]

Any help/hints would be appreciated. The TAs (teacher assistants) can't help us with our problem set questions, so I'm stuck on this one. I really suck at proving identities. :(

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# Homework Help: Identity proof

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