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Homework Help: Problem with partial derivatives

  1. Mar 19, 2009 #1
    1. The problem statement, all variables and given/known data
    suppose that f(x,y)=f(y,x) for all (x,y)[tex]\in[/tex]R^2 show that
    (for partial derivative )
    Df/Dx (a,b)=Df/Dy(b,a)
    2. Relevant equations

    3. The attempt at a solution
    i don't know how to start
    can i do like this
    set g(x,y)=f(y,x)
    f o g (x,y) =f(x,y)
    then how to continue ?
  2. jcsd
  3. Mar 19, 2009 #2


    Staff: Mentor

    Re: proof

    Since you don't have much to go on, I'd suggest that you use the definition of the partial derivative for each of the two partials.
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