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- Nov 23rd 2013, 01:21 AManil86Prove the following
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- Nov 23rd 2013, 08:09 PMchiroRe: Prove the following
Hey anil86.

I'd suggest you take a look at the sum-to-product and product-to-sum identities (and keeping in mind the relation cos(ix) and cosh(x) and so on).

List of trigonometric identities - Wikipedia, the free encyclopedia - Nov 24th 2013, 03:47 AMIdeaRe: Prove the following
Restating the problem:Given

or

Show

Let

and

and

so that

Now use the identity