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Homework Help: Help with integral of Log

  1. Jan 10, 2009 #1
    1. The problem statement, all variables and given/known data

    [tex]\int[/tex][tex]\int-xlogy dy dx[/tex]

    the only problem i have is finding the integral of logy
    i know i have to integrate my parts with u = logy and dv=dy
    the book says the the integral of logy is ylogy-y but isn't the derivative of logy equal to 1/ylna where a is the base?
    so isn't the integral of logy equal to ylogy-y/ln10 because of the base 10?
    can someone clarify this for me?
     
  2. jcsd
  3. Jan 10, 2009 #2

    jgens

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    Gold Member

    I know some calculus books (especially the older ones I have looked at) use log(y) to designate the natural logarithm. Are you certain this isn't the case?
     
  4. Jan 10, 2009 #3
    oooo it is thanks makes a lot more sense now
     
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