AP Calculus
posted by Corin .
I need to find the integral:
int:(x^2+2x+3)/(x^3+3x+9) dx
I think I am supposed to use the rule: int:1/u du=lnu+C
But I don't know what to do first.
Thanks for your help! :)
Oh and the answer the back of my book gives is (1/3)lnx^3+3x^2+9x+C

AP Calculus 
bobpursley
This is an integral in the form of
INT f'(x)/f(x) dx
it integrates to ln (f(x))
http://en.wikipedia.org/wiki/Table_of_integrals 
AP Calculus 
Corin
Thanks for your help! :)
I think I got the answer!
Thanks1
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