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Homework Help: How to do this kind of integral?

  1. Apr 26, 2008 #1

    nicksauce

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    1. The problem statement, all variables and given/known data
    I want to evaluate, using residue calculus, the following
    [tex]\int_0^{\infty}\frac{xdx}{1+x^4}[/tex]
    I can't find any kind of formula for this kind of integral though. We just know [tex]\int_{-\infty}^{\infty}\frac{P(x)dx}{Q(x)}[/tex], however that would give 0 in this case as the function is odd. Any pointers?

    2. Relevant equations



    3. The attempt at a solution
     
    Last edited: Apr 26, 2008
  2. jcsd
  3. Apr 26, 2008 #2

    nicksauce

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    Err... figured it out. Just have to use a the contour with a quarter-arc, then along the y-axis, then the x-axis...
     
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