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Homework Help: Differentiate this, i need help

  1. Feb 25, 2007 #1
    y=ex(x is suppost to be smaller and on the top right of e)/x squared

    i a suppost to differentiate this, well i wrote -2ex/x cubed+ ex/ x sq.

    now u probabl might be confused by the way i wrote it since i dont know how to put the right things for my problems,

    well i set up the problem how do i figure out the answer,

    i know the answer but how do i figure it out
     
    Last edited: Feb 25, 2007
  2. jcsd
  3. Feb 25, 2007 #2

    ranger

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    Is this what you are getting at y = ex/x2?

    Would it help if you rewrite it as a product rule:
    ex.x-2
     
  4. Feb 26, 2007 #3

    cristo

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    This is correct.
     
  5. Feb 26, 2007 #4

    Gib Z

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    [tex]y=\frac{e^x}{x^2}[/tex]
    Let [itex]u=e^x[/itex] and [itex]v=x^2[/itex].

    By the quotient rule, the derivative is [tex]\frac{u'v-v'u}{v^2}[/tex]
     
  6. Feb 26, 2007 #5

    cristo

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    I must've skipped over this, and so didn't notice that you wanted to know how to get the answer!!

    Well, anyway, now you've got two ways; using the product rule as shown by ranger, or the quotient rule given by Gib Z.
     
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