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Homework Help: Convergence of Integral

  1. Apr 1, 2008 #1
    1. The problem statement, all variables and given/known data
    State whether the problem is convergent or divergent and if its convergent solve the integral. Integral from 0 to inf of (sinx)/(1+cos^2(x))dx

    2. Relevant equations
    there isnt really an equation for this, I dont think.

    3. The attempt at a solution

    Im not really sure how to even start this problem. I know it converges, and I know the answer is pi/4 (the book has the answer) but I am stuck on how to figure out that it A) converges and B) how to solve it.

    *I know there are several tests you can use to test for convergence (ratio test, p test, etc.) but im not sure which one applies here.
  2. jcsd
  3. Apr 1, 2008 #2


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    Science Advisor
    Homework Helper

    It doesn't converge. Find the antiderivative, use u=cos(x). Evaluate it between 0 and L and then let L->infinity. Does it approach a limit?
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