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Why the answers are different if theyre the same

  1. Apr 28, 2007 #1
    why the answers are different?
    -integral of 2 ln(x)
    -integral of ln(x)^2
     
  2. jcsd
  3. Apr 28, 2007 #2
    by ln(x)^2 do you mean (ln(x))2 or ln(x2)? If you meant the second one then your answers should not be different as they are exactly the same, however, if you meant the first then the two functions are not equal and you should not expect equivalent answers.
     
  4. Apr 28, 2007 #3

    quasar987

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    [tex]\ln(x^2)=2\ln(x)[/tex]. More generally, it is a property of logarithms that [tex]\log_a(b^c)=c\log_a(b)[/tex].
     
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