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In(x)/(1+exp(x)) from 2 to ∞?

  1. Nov 25, 2011 #1
    determine whether the integral In(x)/(1+exp(x)) from 2 to ∞? converges or diverges?
  2. jcsd
  3. Nov 26, 2011 #2


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    What is this function In(x)? Do you mean ln(x)? Assuming so, I think you can do a simple comparison test:

    0 < ln(x) / (1+exp(x)) < x / (1+exp(x)) < x / exp(x)

    And it's fairly easy to show the integral of x/exp(x) converges.
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