The integral is t(4+9t)^(1/2) dt I have tried u-sub and integration by parts but i cant figure it out. u=4+9t du=9 Does not help because i still have that t to deal with. I have spent more time then i want to admit trying to figure it out, and there are plenty more in the hw. Can someone help me out so i can move on with the assignment? Thanks guys/gals.