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Homework Help: Two integrals that I don't know how to solve

  1. Oct 3, 2011 #1
    1. The problem statement, all variables and given/known data
    There are two integrals that I don't know how to solve. I'm fairly certain the preceding work that led me to these integrals is correct.

    2. Relevant equations
    1. ∫sin (x) / (csc (x) + cot (x))
    2. ∫x^(2) / (1 - x)

    3. The attempt at a solution
    U substitution didn't work for either integral. Is integration by parts the correct way to go?

    Thank You
  2. jcsd
  3. Oct 3, 2011 #2


    Staff: Mentor

    Re: Integrals

    Integration by parts is NOT the way to go!

    Also, don't forget the "dx". As the integrals get more complicated, omitting this symbol will definitely cause problems.

    For the first integral, use the basic trig identities to get everything in terms of sine and cosine.

    For the second, one approach is to use polynomial long division to divide x2 by 1 - x. Or, you can write x2/(1 - x) as (x2 - 1 + 1)/(1 - x), and split into two integrals.
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