
integration problems
i'm having trouble (as always), starting these problems. hints on how to start would be nice.
evaluate the integrals
a).
i think i have to do this by integration by parts, so i have:
.
though i think this is wrong.
b). .
again, i think it's integration by parts, but the 4 and 3 are messing me up
c).
i have
the square root is messing me up, so again, i don't think i selected the parts correctly.
any help on how to get started would be nice.
thank you,
Scott

Hello, scottie.mcdonald!
The third one requires a "simple" substitution . . .
Let: .
. . Then: .
Substitute: .
. .
Backsubstitute: . .[1]
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
We could stop here, but we can simplify the answer further . . .
Multiply the fracton by
. .
Then [1] becomes: .
. . . . . . . . . . . .
. . . . . . . . . . . .
Pull something like this on any of your exams,
. . and I'll guarentee that you'll surprise/impress/terrify your teacher.

ha ha yeah, my teacher would look at me with wonder if i thought about rationalizing at the end (though now i'm always going to look for that).
Thanks for the help =)