
trig integrals
i have a calc test coming up and im not sure how to do the following, if you could show me how, it would be greatly appreciated...thanks!
1. integral (where b= pi/2, a = 0) sin^2x cos^2 x dx
2. integral (where b= pi/4, a = 0) sec^4 x tan^4 x dx
3. integral tan^6(ay) dy

Hello, skabani!
Here are the first two.
. . I'll let someone else explain the third one.
We need two identities:
. .
We have: .
The integral becomes: .
And we have: . . Got it?
We have: .
The integral becomes: .
Let
Substitute: . . Okay?

great thanks so much!
i hope someone can help me out with the third one, before tonight, for my exam tomorrow...

For the last one, first put then just worry about Now, note that,
Make it in the same fashion for