I am attempting to solve a physics problem, and in the process am getting tripped up by an integral:(adsbygoogle = window.adsbygoogle || []).push({});

integrate from 0 to pi (sin(theta)cos(theta) d_theta)

sorry, I don't know how to use the symbols =/

at any rate, I substitute U for sin theta, du is cos theta, and integrate and of course I get sin^2(theta)/2 which of course equals 1 - cos 2(theta), evaluated from zero to pi, which gives me an answer of zero.

In the context (potential on the surface of a sphere), this doesn't make any sense - so obviously my math must be wrong somewhere. if someone can point it out, then i'd be much obliged.

Thanks

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# Is this correct?

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