# Integral of xf(x)dx

• Apr 6th 2010, 04:10 PM
Integral of xf(x)dx
I tried doing integration by parts, but I end up getting the wrong answer, help?
• Apr 6th 2010, 04:58 PM
chiph588@
Let $u=x\implies du=dx$ and $dv=f(x)dx\implies v=\int f(x)dx$.

So we get $\int xf(x)dx = x\int f(x)dx -\iint f(x)dx dx$.

Is this the answer you're looking for?