Find the volume of the paraboloid $z = 3 - x^2 - y^2$

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Find the volume below the graph of the paraboloid $z=3-x^2-y^2$. I have to calculate this integral without using polar coordinates.

The integration's limits are not specified so I've assumed that the volume is between the $xy$ plane and the graph. If so, I end up having $0 \leq z \leq 3-x^2-y^2$ as a domain of integration but I don't know how to use it in order to write and calculate the integral.

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The bounds on $x$ and $y$ are $-\sqrt3$ to $\sqrt3$, as the intersection of the paraboloid with the $xy$-plane is the circle $x^2+y^2=3$. This gives us the integral $$\int_{-\sqrt3}^{\sqrt3}\int_{-\sqrt{3-x^2}}^{\sqrt{3-x^2}}\int_0^{3-x^2-y^2}1\,dz\,dy\,dx$$ which I leave to you to evaluate.