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Did I simplify this right?

  1. Apr 22, 2012 #1
    1. The problem statement, all variables and given/known data

    y - 1 / 3 = 1 / 3 (x - ln(1/3))

    3. The attempt at a solution

    y - 1 / 3 = 1 / 3 (x - ln(1/3))

    0 = 1 /3 x - 1/3 ln(1 / 3) + 1 / 3 - y

    0 = x - ln(1 / 3) + 1 - 3y

    I don't see any problem with it.

    Text book says it's wrong. >_<

    The answer is = x - 3y + (1 + ln3) = 0
     
  2. jcsd
  3. Apr 22, 2012 #2
    You have pretty much the same thing, except that they have used

    [tex]\text{ln}( 1/x ) = \text{ln}( x^{-1} ) = -\text{ln}(x)[/tex]

    to convert [itex]\text{ln}(1/3)[/itex] to [itex]-\text{ln}(3)[/itex].
     
  4. Apr 22, 2012 #3

    SammyS

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    Your result and the book answer are equivalent.

    ln(1/3) = ln(3-1) = (-1) ln(3)
     
  5. Apr 22, 2012 #4
    Thank you very much. :]


    Thank you very much. :]
     
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