Question

need help with an integral :)

Answer 1

\[\int\limits_{}^{}e ^{2y}\sqrt{1+64e ^{4y}}dy\]

Answer 2

not sure what I should use for u in u substitution for this one

Answer 3

have you tried using whats under the root?

Answer 4

but that would just give me du=\[256e ^{4y}dx\] whose inverse wouldn't quite cancel out with the \[e ^{2y}\] though, right?

Answer 5

whoops dy not dx

Answer 6

yeah that wouldn't work, try subing u = e^2y then

Answer 7

okay just a sec

Answer 8

that would leave you with 1+64u^2 inside the root

Answer 9

its one of those tedious trial and error things

Answer 10

aha, yes you are right. I got the right answer. Thanks so much :)

Answer 11

cool))