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Homework Help: Solving for Partials

  1. Jun 2, 2007 #1
    "Solving for Partials"

    This is for my revision and I have the answer sheet:

    I'm meant to find ∂u/∂x for x = u + v + w, y = u^2 + v^2 + w^2, z = u^3 + v^3 + w^3

    That as far as I can tell, by a miracle, is meant to equal:

    ∂u/∂x=(vw)/((v − u)(w − u))

    All the question says apart from find this is "Solving for Partials".

    I can't find anything that looks like this in my notes and google comes up empty. What's going on here?
  2. jcsd
  3. Jun 2, 2007 #2


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    Well, if you want to solve for the partial derivative of u with respect to x, it seems that you ought to partially differentiate each equation with respect to x. What kind of equations do you get when you do that?
    Last edited: Jun 2, 2007
  4. Jun 3, 2007 #3
    key word : implicit differentiation
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