Thanks guys for the help provided.
Hello, tester85!
I'll explain the first one for you.
It's quite challenging and uses a technique you may not have seen.
Integrate by parts . . .
. .
We have: .
Integrate by parts (again):
. .
We have: .
. .
. .
Multiply by
. . . . . . . .
Factor: .
. . . . . . . . . . .
Therefore: .