How do you prove the partial derivative identity with three variables?

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SUMMARY

The discussion focuses on proving the partial derivative identity for three variables, specifically that (dx/dy)(dy/dz)(dz/dx) = -1 when f(x,y,z) = 0 is differentiable. The solution involves recognizing the relationships x = x(y,z), y = y(z,x), and z = z(x,y) and applying implicit differentiation. The key step is differentiating the function with respect to x, leading to the equation df/dx + df/dz(dz/dx) = 0, which is essential for deriving the identity.

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Homework Statement



Suppose that the equation f(x,y,z)=0 can be solved for each of the three variables as a differentiable function of the other two. Prove that:

(dx/dy)(dy/dz)(dz/dx)=-1

Homework Equations





The Attempt at a Solution


In the case of two variables where one is a function of the other, dy/dx = -(df/dx)/(df/dy), but I can't figure out how this works with 3 variables.
 
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so to get you started, first we know
x=x(y,z)
y=y(z,x)
z=z(x,y)


so fa(x,y,z) = f(x,y,z(x,y))=0 the differentiating w.r.t x gives

df/dx +df/dz(dz/dx)=0
 
Thanks. I was able to figure it out from there.
 

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