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Homework Help: Implicit Differentiatoin question

  1. Sep 26, 2005 #1
    Hello all.
    I am given the equation [tex] (x^3 y^4)^5 = x-y [/tex]

    my derivative is [tex] 1/ (15x^2 20y^3(x^3y^4)^4)=y' [/tex]

    But the book says: [tex] y'=(1-15x^14y^20)/(1+20x^15y^19)[/tex]

    Where did I go wrong?

    Thanks so much
  2. jcsd
  3. Sep 26, 2005 #2


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    Homework Helper

    You didn't differentiate the left side correctly. Try again.
  4. Sep 27, 2005 #3


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    Homework Helper

    You need to put curly brackets around all of your power if there is more than one character involved - like so,

    [tex] y'=(1-15x^{14}y^{20})/(1+20x^{15}y^{19})[/tex]
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