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Math Help - Int (lnx)/x^2

  1. #1
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    Int (lnx)/x^2

    Integrate (lnx)/(x^2) dx

    (Part of a question to determine convergence or divergence)
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  2. #2
    No one in Particular VonNemo19's Avatar
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    Quote Originally Posted by jlmills5 View Post
    Integrate (lnx)/(x^2) dx

    (Part of a question to determine convergence or divergence)
    Try integration by parts with

    u=\ln{x} and

    dv=\frac{1}{x^2}dx
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  3. #3
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    Ah, I see what I did...or rather wasn't doing. I used parts like you said but apparently was not simplifying the answer the way the key does. Thanks.
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  4. #4
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    I need to find the limit as b -> infinity for [-(lnx+1)/x] from 1 to b.

    How do I do this...do I use L'Hopital's rule for the infinity portion? I'm getting -1 as the answer but this isn't right. Any suggestions?
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  5. #5
    No one in Particular VonNemo19's Avatar
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    Quote Originally Posted by jlmills5 View Post
    I need to find the limit as b -> infinity for [-(lnx+1)/x] from 1 to b.

    How do I do this...do I use L'Hopital's rule for the infinity portion? I'm getting -1 as the answer but this isn't right. Any suggestions?
    should be +1. check your signs.
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