Is there a parametrization of a hyperbola by functions x(t) and y(t) both birational?
Consider the hyperbola . I am aware of some parametrizations like:
1.
2.
3.
4.
The first and the second are by rational functions x(t) and y(t). But the functions are not birational(i.e. with rational inverse of each).
Is there a parametrization where:
- x(t) is rational with inverse also rational, and
- y(t) is rational with inverse also rational?
Is possible, to find a parametrization where both are rational and at least one of the has inverse rational?