- #1

fk378

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## Homework Statement

Given the partial derivative df/dx= 3-3(x^2)

what is d^2f/dydx?

I'm not sure if the answer would be 0, since x is held constant, or if it would remain 3-3(x^2) (since df/dx is a function of x now?)

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- Thread starter fk378
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- #1

fk378

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- 0

Given the partial derivative df/dx= 3-3(x^2)

what is d^2f/dydx?

I'm not sure if the answer would be 0, since x is held constant, or if it would remain 3-3(x^2) (since df/dx is a function of x now?)

- #2

G01

Homework Helper

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You are given a function:

[tex]g(x)=3-3x^2[/tex]

You want to find: [tex]\frac{\partial g}{\partial y}[/tex]

What is that derivative? Now, what if: [tex]g(x)=\frac{\partial f}{\partial x}[/tex]

Does this change the partial derivative of g with respect to y?

- #3

Dick

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- #4

HallsofIvy

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I, and I suspect many who read your post, was momentarily taken aback since I thought you were "holding x constant" through both derivatives. But you are correct: since this function does

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