# Ahh this one has been bugging me!

1. Dec 7, 2007

### tnacrew

Δƒ/Δx and Δƒ/Δy. ƒ(x,y) = xy² + x²y

anyone able to calculate?

2. Dec 7, 2007

### ozymandias

I'm not sure what you mean by $$\frac{\Delta f}{\Delta x}$$. Do you mean $$\frac{\partial f}{\partial x}$$?

At any rate, why don't you tell us what you've tried and where you get stuck?

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Assaf
Physically Incorrect

3. Dec 7, 2007

### HallsofIvy

Staff Emeritus
Whether you mean the partial derivatives or the "difference quotients" those are both pretty straightforward by methods you learned in elementary calculus. How have you tried to do them?