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Homework Help: Simple integral

  1. Oct 31, 2005 #1
    this integral can be solved without u-subsitution however, I get a different answer when I use u-sub.

    [tex]\int \frac{6}{x-6} dx [/tex]

    [tex]u=x-6[/tex]

    [tex]du=dx[/tex]

    [tex]\int \frac{1}{6u}=\frac{1}{6}ln(x-6)[/tex]

    if U-sub wasnt used, then the answer would be 6ln(x-6)

    what am I doing wrong in the subsitution?
     
  2. jcsd
  3. Oct 31, 2005 #2

    James R

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    With the substitution, the integral is:

    [tex]\int \frac{6}{u} du[/tex]

    not

    [tex]\int \frac{1}{6u} du[/tex]
     
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