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I found this question in an old real analysis text book, (so old the cover had come off) I graphed it on wolfram alpha, and it looks like an almost odd function. I think the integral evaluates to zero. Would anyone care help prove? (assuming I'm right)

Simon S
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ptr64
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1 Answers1

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$\sin 4x = 2 \cos 2x \sin 2x = 4 (2 \sin^2 x -1 ) \sin x \cos x $

Substitute $t = \sin x$