(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Let f(x,y)=1−x[itex]^{2}[/itex]−y[itex]^{2}[/itex]. Find the point at which

[itex]\frac{\partial f}{\partial x}[/itex] = [itex]\frac{\partial f}{\partial y}[/itex] = 0

and illustrate graphically the nature of the surface z = f (x, y) at this point.

3. The attempt at a solution

Just did the partial derivatives and got 2x=2y=0 hence x=0 and y=0

So illustrating z=f(x,y) at this point give z=1

Creating a contour plot I get the plot attached below.

This question is part of a difficult assignment I got from uni but this question seems way to easy in comparison to the rest of the assignment. I just want to make sure there isn't something I missed or is it really this simple?

Thank you

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# Homework Help: Partial Derivative and Graph

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