The question asks to prove the following by writing each sine and cosine function as a sum of exponentials of arguments inwt or imwt:(adsbygoogle = window.adsbygoogle || []).push({});

integral from -pi/w to pi/w (cos (nwt)cos(mwt) dt) = {0 for n not equal to m, pi/w for n=m not equal to 0 , 2pi/w for n=m=0

Would I write the cosine funtion in the exponential form e^x+e^-x/2 and then solve by using different valuse for n and w for the one the is equal to 0 when n is not equal to m? I'm confused.

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# Help understanding question

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