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Homework Help: How do you take the natural logs?

  1. Feb 19, 2005 #1
    how do you take the natural logs??

    I think this is why I can't do my problems, maybe i'm missing some basic concepts.

    ok, so let [tex] L({\theta}) = \theta^{-2n} \prod y e^{-(1/theta)}\sum y [/tex]

    taking the natural log, I get

    [tex]ln L(\theta) = -2nln\theta + ln \prod y - 1/\theta \sum yi [/tex].

    I dont know, how did they do that?

    and later, I will need to differentate it too, but and I dont know how to do it either. but for that one, how did they do it?
     
  2. jcsd
  3. Feb 19, 2005 #2

    Fredrik

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    I can't make sense of what you've written. Indices and parentheses would help. Anyway, whatever that first expression is supposed to be, there's a good chance you will be able to simplify the logarithm considerably by using log(xy)=log x + log y repeatedly.
     
  4. Feb 19, 2005 #3

    dextercioby

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    That product wrt what is it evaluated...?

    Daniel.
     
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