# having trouble with setting up integral by parts

• Oct 12th 2010, 11:26 AM
solidstatemath
having trouble with setting up integral by parts
I understand how to solve integrals by parts. My problem lies in setting up the variables so that I can begin solving it.

Scanned is my work and how I set up the variables in what I believe are good except for the v and dv.

If I can get v and dv correct then I know how to solve this but need a little kick start.
• Oct 12th 2010, 11:31 AM
harish21
If $dv = sin(2x) dx$ , then $\displaystyle{v = \frac{-cos(2x)}{2}}$
• Oct 12th 2010, 11:47 AM
solidstatemath
• Oct 12th 2010, 11:50 AM
harish21
$\displaystyle{ \int cos(2x) dx = \frac{sin(2x)}{2}}$
• Oct 12th 2010, 12:04 PM
solidstatemath
So we would then multiply 1/2 by [1/2 * sin(2x)] = 1/4 * sin(2x)?
• Oct 13th 2010, 11:02 AM
Pandevil1990
Quote:

Originally Posted by solidstatemath
So we would then multiply 1/2 by [1/2 * sin(2x)] = 1/4 * sin(2x)?

Yes...