Easy integration by parts question.

[Kuma]

Homework Statement

Hi

This is something i don't remember what I'm supposed to do. So anyway here goes.

For example if my function was

xe^yx and i wanted to integrate with respect to dx

then i do an integration by parts with these variables:

u = x dv = e^yx

now my question is, when i try to find du do i differentiate with respect to x? same goes for dv, do i integrate with respect to dx?

suppose instead i chose
u = e^yx and dv = x

then du would be ye^yx?

Hopefully that was clear enough.

 

[fss]

u = x
dv = e^yx

when i try to find du do i differentiate with respect to x?

Yes.

same goes for dv, do i integrate with respect to dx?

Technically, your "dv" expression should be:

dv = e^yxdx

...so there's not much to be confused about on that part, at least.

 

[Kuma]

ok thanks

 

[Liquidxlax]

remember you need

u du v dv

you know u=x dv=e

du=dx v=(1/y)e^yx