I have been asked to explain(adsbygoogle = window.adsbygoogle || []).push({}); without evaluating the integralswhy the integral of x cos x from 0 to pi/2 is positive and the integral of x cos x from pi/2 to pi is negative. Also would I expect x cos x from 0 to pi to be positive, zero or negative??? And why ???

How can I do this without evaluting it??? some help would be much appreciated, thanks!

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# Homework Help: Integral - help needed please

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