11.12.2 The hyperbola in the plane: hyperbola
See section 12.11.2 for hyperbolas in space.
The hyperbola command draws hyperbolas and other conic sections.
hyperbola can take parameters in different forms.

hyperbola can take one parameter, a second degree equation in the
variables x and y (or an expression which will be set to zero).
hyperbola returns and draws the conic section given by the
equation.
Input:
hyperbola(x^2  2*y^2  1)
Output:
 hyperbola can take three parameters; either three
points or two points and a real number. The first two points will
be the foci of the hyperbola and the third argument will be either a
point on the hyperbola or the length of the semimajor axis.
hyperbola returns and draws the hyperbola.
Input:
hyperbola(i,i,i+1)
Output:
Input:
hyperbola(i,i,1/2)
Output:
Note that if the third argument is a point on the real axis, the
real affix of the point won’t work, it needs to be specified with
the point command.