# Thread: Intergrating Exponential Functions

1. ## Intergrating Exponential Functions

How do you evaluate this:
INT[e^(sin*pi*x) cos*(pi)x dx]

do I let u=sin(pi)x so du/(cos(pi)x)=dx

then, I plug in the values but I got a differernt answer from the book...can someone please help?

2. Originally Posted by got_jane
do I let u=sin(pi)x so du/(cos(pi)x)=dx
The problem is that you're not applyin' the chain rule here.

(See my signature for LaTeX typesetting.)

3. Originally Posted by got_jane
How do you evaluate this:
INT[e^(sin*pi*x) cos*(pi)x dx]

do I let u=sin(pi)x so du/(cos(pi)x)=dx

then, I plug in the values but I got a differernt answer from the book...can someone please help?
$u=sin(\pi x)$
$du=\pi cos(\pi x) dx$

That should help...