This has been posted before although I've come across it and got a differant answer from https://www.physicsforums.com/archive/index.php/t-108378.html(adsbygoogle = window.adsbygoogle || []).push({});

x sinx cosx dx using the identity sin2x = 2sinxcosx

u = x

du = 1

dv = 1/2 sin 2x

v = -1/4 cos 2x

x sinx cosx dx = -1/4xcos2x - Int -1/4cos2x + c

= -1/4xcos2x + 1/8sin2x + c

Right?

And I need some help to work out:

Integral of x^3cosx^2

I'm always getting confused with powers on the trig for some reason.

Thankyou

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# Integral - is this correct?

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