# Homework Help: Declaring the domain of a function of two variables.

1. Oct 3, 2012

### lo2

1. The problem statement, all variables and given/known data

I have this function of two variables:

$f(x,y)=\sqrt{4xy-3y^2}$

Where I have to declare the domain of the function.

2. Relevant equations

Since you cannot take the square root of something negative, when dealing with real numbers. The square root has to be zero or above.

3. The attempt at a solution

Well I just wanted to know if this is a sufficient answer:

$D_f = \{(x,y) = 4xy-3y^2 \geq 0 \}$

2. Oct 3, 2012

### HallsofIvy

Yes, it is. That is the "natural domain" of the given function.