The given hyperbolic paraboloid is $z=xy$. How do I find the distance $r$ from a point on the surface to the $z$-axis?
I used a function grapher to visualize the 3-D surface. But I am unable to understand how to calculate the required distance $r$. I am very poor at interpreting 3-D surfaces. Any help is much appreciated!
Given any point $(x, y, z)$, the distance to the $z$ axis is $\sqrt{x^2 + y^2}$. This has nothing to do with the point lying on a paraboloid.