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Function - derivative (help!)

  1. May 22, 2010 #1
    function --- derivative (help!)

    1. The problem statement, all variables and given/known data

    [PLAIN]http://img15.imageshack.us/img15/705/123gm.jpg [Broken]

    but instead of f(x)=x^-2, let f(x) = x^(1/2 )

    3. The attempt at a solution

    So, I did

    [ (x+h)^1/2 - (x)^1/2 ]/ h

    But im not sure how to simplify it. What would be my next step? Thanks alot :)
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. May 22, 2010 #2


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    Re: function --- derivative (help!)

    Rationalize the numerator. (Like rationalizing the denominator, only opposite) :cool:
    Last edited by a moderator: May 4, 2017
  4. May 22, 2010 #3
    Re: function --- derivative (help!)

    Ah okay, yea I got it now. thanks :)
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