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Homework Help: Evaluate the improper integral.

  1. Jun 28, 2008 #1
    [tex]\int_0^\infty \; \frac{ \ln\;(1+x^2)}{ x^2+2x\;\cos\;\theta + 1 }\;\;dx[/tex]

    [tex]\theta \in \mathbb{R}[/tex]
  2. jcsd
  3. Jun 29, 2008 #2


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  4. Jun 29, 2008 #3
    Indeed why?

    But If you don't know how to do this I think a contour integration is the best approach.
  5. Jun 29, 2008 #4


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    From Maple:

  6. Jun 29, 2008 #5
    Oh wow, thats a very insightful answer.
  7. Jun 30, 2008 #6

    Gib Z

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    Differentiation under the integral sign looks like it'll work here.
  8. Jun 30, 2008 #7
    What function should you take: [tex]\ln(ax^2 +1) [/tex]?
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