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Homework Help: Integral of (lnx)^2

  1. Dec 4, 2004 #1
    can anyone help me ?? i cant seem to do it i dont know what to do i tried by parts and substitution
     
  2. jcsd
  3. Dec 4, 2004 #2

    Tide

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    HINT:

    [tex]\int (\ln x)^2 dx = \int \frac {dx}{dx} (\ln x)^2 dx[/tex]
     
  4. Dec 4, 2004 #3
    sorry to say but i dont get that hint , can u exlain more plz




    thanks
     
  5. Dec 4, 2004 #4

    shmoe

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    When you tried integration by parts, how did you break it up? Do you know how to find the simpler integral [itex]\int\ln(x)dx[/itex] by parts?
     
  6. Dec 4, 2004 #5

    Tide

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    It's just integration by parts:

    [tex]\int (\ln x)^2 dx = \int \frac {dx}{dx} (\ln x)^2 dx = x (\ln x)^2 - \int x \frac {d (\ln x)^2}{dx} dx[/tex]

    You should be able to handle the rest.
     
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