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Homework Help: Find the derivative

  1. May 10, 2010 #1
    I am having difficulty figuring this one, any guidance will be appreciated.

  2. jcsd
  3. May 10, 2010 #2


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    We cannot guide you until you show us where you get stuck. What kind of methods have you tried to use so far?
  4. May 10, 2010 #3
    This is what I have so far.

    I believe i use this rule d/dx log a ^ u = 1/(lna)u

    so ln = 1
    a = ln
    u = (1+e^sqrtX)/(2-e^cosx)

    now i need to take the derivative of u, does e^sqrtX = e^sqrtX or is it e^sqrtX * derivative of sqrtX making it e^sqrtX * 1/2sqrtX

    d/dx u =
  5. May 10, 2010 #4


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    This 'rule' makes no sense whatsoever.

    This is also pretty hard to read. Yes [itex]\exp(\sqrt{x})=\exp(\sqrt{x})[/itex]. This is no surprise since everything equals itself. What you probably mean is [itex]\frac{d}{dx}\exp(\sqrt{x})=\exp(\sqrt{x})[/itex]. That is wrong since you have to use the chain rule therefore your second guess,[itex]\frac{d}{dx}\exp(\sqrt{x})=\exp(\sqrt{x}) \frac{1}{2 \sqrt{x}}[/itex], is correct.
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