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Implicit Differentiation Question

  1. Mar 11, 2012 #1
    1. The problem statement, all variables and given/known data

    2x[itex]^{3}[/itex]-3x[itex]^{2}[/itex]y+2xy[itex]^{2}[/itex]-y[itex]^{3}[/itex]=2

    2. Relevant equations



    3. The attempt at a solution

    6x[itex]^{2}[/itex]-(6xy+3x[itex]^{2}[/itex]y')+(2y[itex]^{2}[/itex]+4xyy')-3y[itex]^{2}[/itex]y'=0

    y'=[itex]\frac{-6x^{2}+6xy-2y^{2}}{-3x^{2}y+4xy-3y^{2}}[/itex]


    My text's solution is the same answer but with every every term having the opposite sign.

    I don't see my error and I'm trying to determine why my answer is incorrect.

    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Mar 11, 2012 #2
    Your answer is correct! Remember you can multiply by [itex]\frac{-1}{-1}[/itex] and the result is the same (multiplying by 1).
     
  4. Mar 11, 2012 #3
    How did I not catch that?:redface:

    Thanks!
     
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