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    Hello everyone,

    I need to test the integral of lnx/(e^x) between 1 and infinity for convergence.

    I tried to integrate this function, but I can't do it (either by parts or by substitution). So I suppose that I need to use the comparison test. So I checked the answer (and apparently the integral converges), so I am trying to find a function which is greater than lnx/(e^x) between 1 and infinity, and that has an integral which also converges.

    I tried (lnx)/x, but it diverges.

    Could you help me find a function greater than lnx/(e^x), that has an integral which converges between 1 and infinity?

    Thanks
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    Have you tried lnx over higher powers of x?
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    Why not use \log (x) < x ?
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    (Original post by Kolya)
    Why not use \log (x) < x ?
    Oh! that totally makes sense!
 
 
 
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