# Integration by Substitution Problem

• Feb 15th 2010, 08:07 AM
xfriendsonfirex
Integration by Substitution Problem
Find the indefinite integral:

$\displaystyle \int (1+\frac{1}{t})^{3}(\frac{1}{t^2})dt$

Perhaps I'm just missing the obvious here, but I can't even determine what to set u to. Any help?
• Feb 15th 2010, 08:34 AM
vince
Quote:

Originally Posted by xfriendsonfirex
Find the indefinite integral:

$\displaystyle \int (1+\frac{1}{t})^{3}(\frac{1}{t^2})dt$

Perhaps I'm just missing the obvious here, but I can't even determine what to set u to. Any help?

Set u=$\displaystyle 1+\frac{1}{t}$

then $\displaystyle du = \frac{-1}{t^2}dt$

Clear now?
• Feb 15th 2010, 08:43 AM
xfriendsonfirex
Crystal. I feel stupid now. Haha. Thanks!
• Feb 15th 2010, 08:52 AM
vince
Quote:

Originally Posted by xfriendsonfirex
Crystal. I feel stupid now. Haha. Thanks!

yeah, i feel bad for answering so directly. i should have hinted instead. it was really something you should have seen. you are nowhere near ready for an exam, based on this, my friend.