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

Prove the identity:

Cosh(x) + Cosh(y) = 2Cosh[(x+y)/2]Cosh[(x-y)/2]

2. Relevant equations

Cosine sum-to-product

http://library.thinkquest.org/17119/media/3_507.gif

3. The attempt at a solution

Can you use the same formula for Cosine sum to product for hyperbolic cosine?

Thanks!

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# Homework Help: Hyperbolic cosine

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