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Integrating a logarithmic function

  1. May 2, 2004 #1

    Math Is Hard

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    I noticed than in the chapters I am studying now that while they give us a formula for taking the derivative of log base a of x, I can't find a correspoding formula for finding the integral of log base a of x.
    We have a table of integrals in the back of the book, but I only see integrals pertaining to forms of ln x.
    So.. am I missing something? Does it not exist? Is it something so ugly I don't even want to know about it??

    Thanks!
     
  2. jcsd
  3. May 2, 2004 #2
    [tex]\log_a{x} = \frac{\ln{x}}{\ln{a}}[/tex]

    cookiemonster
     
  4. May 2, 2004 #3

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    ok, so I use change of base to convert. Then to integrate, do I use substitution, or is it simpler than that? thanks.
     
  5. May 2, 2004 #4
    ln(a) is a constant. It comes right out front.

    cookiemonster
     
  6. May 3, 2004 #5

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    Oh crud! I walked away from the computer after my last post and then all of a sudden it hit me like a ton of bricks!!! :eek:
    thanks, CM. You are going to be a big hit at CalTech. :biggrin:
     
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