Do you always have to use u-substitution? i.e. sometimes will you get a different answer to if you didn't? Im asking because I had the integral ∫sinxcosx dx between 0 and π/2 and the answer was 1/2 but I got 0.(adsbygoogle = window.adsbygoogle || []).push({});

∫sinxcosx dx between 0 and π/2=-cos(π/2)sin(π/2)=0 according to my calculations.

What am I doing wrong?

I don't thin this counts as homework style as I am hoping just to find out whether you always have to use u-substitution in certain case using the above question as proof.

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# Do you HAVE always to use u-substitution?

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