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Homework Help: Problem with Integrating

  1. Apr 22, 2010 #1

    silvermane

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    1. The problem statement, all variables and given/known data
    Integrating X^3/((e^x)-1), where we integrate from -infinity to infinity

    3. The attempt at a solution
    We thought about it, and we're not entirely sure if integration by parts is applicable here. Is there a table with this function perhaps?
     
  2. jcsd
  3. Apr 22, 2010 #2

    Dick

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    Re: Integrating...

    That integral doesn't converge as x->(-infinity), does it? The denominator is near 1 and the numerator is near x^3. Are you sure about the limits?
     
  4. Apr 22, 2010 #3
    Re: Integrating...

    it doesnt matter if it converges at -infinity you can just make the upper and lower bounds 0 to infinity and put a coefficient of 2 in front of the integrand
     
  5. Apr 22, 2010 #4

    Char. Limit

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    Re: Integrating...

    That only works if it's an even function, which this isn't.
     
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