SolveCubic app for iPhone and iPad

SolveCubic solves the general cubic equation. Although the solution to the quadratic equation has been known since the 8th century BCE, the solution to the general cubic proved to be elusive until the 16th century.

Whereas the quadratic has a well known, compact, and easily calculated solution the cubic is not so easily dealt with. It is not tractable and consists of several involved steps and requires the use of complex numbers.
As such it lends itself nicely for realization as an app utility.

SolveCubic gives the three roots with real and imaginary components. Additionally the 2D curve is plotted and the behavior can be seen as coefficients are varied.