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Homework Help: Second order partial derivatives

  1. Mar 6, 2009 #1
    1. The problem statement, all variables and given/known data

    if z= f(x) + yg(x), what can you say about zyy explain?

    2. Relevant equations



    3. The attempt at a solution
    z= f(x,yy)
    zyy = d/dy (dz/dy) d(partial derivative)
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Mar 6, 2009 #2

    lanedance

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    Homework Helper

    z = f(x,yy) this not correct, i am not sure what it means

    try taking the partial derivative and see what you get

    remember for partials, the other variable is kept constant during the differentiation, in this case x
     
  4. Mar 6, 2009 #3
    Consider that d/dx (a(x,y) + b(x,y)) = d/dx a(x,y) + d/dx b(x,y).

    Also recall that d/dx (a(x,y)*b(x,y)) = (d/dx a(x,y))*b(x,y) + a(x,y)*(d/dx b(x,y)).
     
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