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What will be the answer of this integral? $$ \int_{-\pi} ^\pi e^{-jw(N-1)}. \frac {\sin^2(wN/2)}{\sin^2(w/2)}\,dw $$

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Is $N$ a positive integer? And $j^2=-1$? Answer: $2\pi$.

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yes N is positve intergal and for every positive integer answer will be 2$\pi$ e.g for N=2 or N=3 answer will remain same or it is dependent on the value of N too? and please if you can show me a step of two on how to get to this answer. thanks – heavenhitman Dec 13 '12 at 14:58

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