# Math Help - integration

1. ## integration

integrate
(9-y)(y^[1/2]) dy

so how do i know which will be my u? so i can obtain my u'?

2. Originally Posted by nuclear123
integrate
(9-y)(y^[1/2]) dy

so how do i know which will be my u? so i can obtain my u'?
If you want to use substitution, set $u \sqrt{y}$.