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Homework Help: Improper Integral

  1. Feb 23, 2013 #1
    1. The problem statement, all variables and given/known data

    [itex]\displaystyle \int_{1}^{\infty} 1/(x^2+ 3 \ |sin x| +2) dx [/itex]

    2. Relevant equations


    3. The attempt at a solution

    [itex]\displaystyle \int_{1}^{\infty} 1/(x^2+ 3 \ |sin x| +2) dx =[/itex]

    [itex]\displaystyle lim_{t\rightarrow \infty} \int_{1}^{t} 1/(x^2+ 3 \ |sin x| +2) dx [/itex]

    Side Work

    [itex]\displaystyle \int 1/(x^2+ 3 \ |sin x| +2) dx [/itex]

    I have now clue how to solve this integral. It can't be simplified. U substitution doesn't work nor does a trigonometric substitution. Once I can solve the indefinite itegral I can solve the rest on my own.

    Thanks in advance.
  2. jcsd
  3. Feb 23, 2013 #2


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    Science Advisor
    Homework Helper

    You can't solve the indefinite integral. You just want to prove the improper integral exists. Try a comparison test.
  4. Feb 23, 2013 #3
    Oh ok thanks that makes since now.
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