Hey guys, I'm doing some multivariable calculus atm, and I need some help with the Domains of some multivariable functions...(adsbygoogle = window.adsbygoogle || []).push({});

1) f(x,y) = 3x^2 + 2y

The problem I'm having here is I basically forget the definition of domain... would it be for all x and y even though there are two whole quadrants this function doesn't hit? (looking at the x-y plane here..)

2) f x(x,y) = 6x

I'm looking at the partial derivative in regards to x here. Would I just assume this is a single variable function and only write the Domain in terms of x? If not, what would I write for the Domain?

3)f y(x,y) = 2

This is the partial derivative in terms of y, I know on the x-y plane it would be defined for all x... is it the same here?

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# Homework Help: Having trouble understanding Domains and Multi Variable Functions

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