How does one use ParametricPlot3D to graph quadric surfaces of the form
x^2/a^2 +,- y^2/b^2 +,- z^2/c^2 = 1
These are hyperboloids of one and two sheets
and equations of the form
which is an elliptic cone.
I have been able to graph an ellipsoid by using the example in the book, which converts the x, y, z coordinate system to sperical coordinates using parametric equations, but so far have not been able to either convert the above equations to a suitable parametric version, or get Mathematica to work without getting a beep.