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Homework Help: Calculus - Derivative of a Function

  1. Oct 8, 2009 #1
    1. The problem statement, all variables and given/known data

    Find the derivative of the function.

    2. Relevant equations


    3. The attempt at a solution

    I have tried this out and came up with an answer that I'm not too confident with, I got:


    I would show my work on here, but don't know how to exactly, so my bad.

    Thanks in advance,
  2. jcsd
  3. Oct 8, 2009 #2
    That's what I got, and my calculator agrees.

    Hint: e^u * e^-u = 1.
  4. Oct 8, 2009 #3
    That's what I get too.
  5. Oct 8, 2009 #4


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    Science Advisor

    you can also note that x= tanh(u) and the derivative of tanh(u) is sech2(u).
  6. Oct 8, 2009 #5
    Wow, thanks a lot for the prompt responses. Normally I'd post something like this on Yahoo Answers and not get an answer for a few days.

    Again, thanks a bunch.

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