(1/pi * int(x*sin(n*x)) from 0 to 2pi)=(2/pi * int(x*sin(n*x)) from 0 to pi)

Uh oh! Wolfram|Alpha doesn't run without JavaScript.

Please enable JavaScript. If you don't know how, you can find instructionshere.Once you've done that, refresh this page to start using Wolfram|Alpha.