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Homework Help: When y is defined as a function of x

  1. Oct 9, 2012 #1
    1. The problem statement, all variables and given/known data

    find [itex]\frac{dy}{dx}[/itex] when y is defined as a function of x by the equation
    y+[itex]e^y = x^2[/itex]

    2. Relevant equations

    3. The attempt at a solution

    hi all,
    do i use implicit differentiation for this? im not really sure how to start...
  2. jcsd
  3. Oct 9, 2012 #2

    Ray Vickson

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    Homework Helper

    Should you use implicit differentiation? Well, why don't you try it, to see what happens?

  4. Oct 9, 2012 #3


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    Science Advisor

    Re: Differentiation

    Differentiate both sides of the equation with respect to x. Since the y on the left side is an unknown function of x, yes, you will need to use implicit differentiation.

    (But, as Ray Vickson implies, even if you were not sure, you should have tried. Much of mathematics is "try and see if it works".)
  5. Oct 9, 2012 #4
    Re: Differentiation

    y'+[itex]e^y y' [/itex] = 2x
    y'(1+[itex]e^y[/itex]) = 2x
    y' = [itex]\frac{2x}{1+e^y}[/itex]
    I think this is the right answer?
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