1135?-1213

Persian mathematician and astronomer who helped lay the foundations for algebraic geometry. In his Treatise on Equations, al-Tusi examined a number of equations, including cubics, and appears to have applied an early version of what would much later come to be known as the Ruffini-Horner method. In fact, this method had been developed earlier by Arab mathematicians, but al-Tusi's writing contains the first extant example of it.