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Homework Help: Check if the function is odd or even

  1. Dec 20, 2008 #1
    i know that if f(x)=f(-x) and if f(-x)=-f(x) then its odd.

    i tried to do this check on this cases
    but its not working

    http://img126.imageshack.us/img126/3942/74448798fv8.gif [Broken]
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Dec 20, 2008 #2


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    These questions aren't always straight forward, you need to understand how the functions behave. Let's consider the first case:

    So you have

    [tex]f\left(-x\right) = \log\left(\frac{1+x}{1-x}\right) = \log\left(\frac{1-x}{1+x}\right)^{-1} = - \log\left(\frac{1-x}{1+x}\right) = -f\left(x\right)[/tex]

    Do you follow?
  4. Dec 20, 2008 #3


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    Science Advisor

    And, of course, most functions are neither even nor odd.
  5. Dec 20, 2008 #4
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