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Homework Help: Property of logarithm

  1. Nov 26, 2011 #1
    Edit: I answered my own question, I guess this thread serves no purpose so mods, you can delete this.

    y = x^2
    ln y = ln x^2
    ln y = 2 ln x

    Can we do the same thing with:

    [tex] y = x^{2/x}[/tex]
    [tex] ln y = ln x^{2/x} [/tex]
    [tex] ln y = \frac{2}{x} x[/tex]

    Would that be correct? I just want to make sure because I used this technique for differentiation.
     
    Last edited: Nov 26, 2011
  2. jcsd
  3. Nov 26, 2011 #2
    Doesn't: [tex] ln y = \frac{2}{x} x[/tex] just make it 2 :p

    But from what I remember about logs, yes you can do that..
     
  4. Nov 26, 2011 #3

    gb7nash

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    Homework Helper

    The OP might have already figured this out, but [itex]ln x^{2/x} = \frac{2 ln(x)}{x}[/itex], not [itex]\frac{2}{x}x[/itex]. Typo maybe?
     
  5. Nov 26, 2011 #4
    Yep, it was a typo.
     
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