Integration by substitution c4 Q

Right so I've got dx as du/e^x and subbed it into the integral
(u-8)u^-1/2 du / e^x
with new limits 16 and 9

not even sure if that's correct but I end up with e^x (well u-8) on the bottom. Do I multiply it out or what?

Cheers

Original post by Jackasnacks

Right so I've got dx as du/e^x and subbed it into the integral
(u-8)u^-1/2 du / e^x
with new limits 16 and 9

not even sure if that's correct but I end up with e^x (well u-8) on the bottom. Do I multiply it out or what?

Cheers

The U-8 will cancel