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Homework Help: Calc question

  1. Sep 3, 2008 #1
    My work is posted below....the problem seems pretty straight forward....but im I dont think IM getting the correct answer...

    any suggestions?

    http://img221.imageshack.us/img221/742/calcek4.jpg [Broken]

    (finding first derivative)
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Sep 3, 2008 #2
    I think everything looks fine up until the last equality:

    [tex]
    \frac {dy} {dx} = \frac {1} {2} ( \frac {1} {x+1} - \frac {1} {x-1} )
    [/tex]

    but

    [tex]
    \frac {1} {2} ( \frac {1} {x+1} - \frac {1} {x-1} ) \neq \frac {1} {2x+1} - \frac {1} {2x-1}
    [/tex]
     
    Last edited by a moderator: May 3, 2017
  4. Sep 4, 2008 #3
    yeap hitman is right.

    Careless error?

    2(x+1) = 2x+2
    and same goes for the next one.
     
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