Omar Khayyám es mi héroe del día por esto:
[...]
Omar Khayyám's solution
As shown in this graph, to solve the third-degree equation $x^3 + a^2x = b$ where $b>0$, Omar Khayyám constructed the parabola $y=x^2/a$, the circle with diameter $b/a^2$ having its center on the positive x-axis and intersecting the origin, and a vertical line through the point above the x-axis where the circle and parabola intersect. The solution is given by the length of the horizontal line segment from the origin to the intersection of the vertical line and the x-axis.[...]
[Cubic function @ Wikipedia]
