Career
A series of observations of lunar and solar eclipses and planetary conjunctions, made by him from 853 to 866, was in fact used by Ibn Yunus. He wrote commentaries on Euclid and Archimedes, and improved Ishaq ibn Hunayn"s translation of Menelaus of Alexandria"s Spherics. He tried vainly to solve an Archimedean problem: to divide a sphere by means of a plane into two segments being in a given ratio of volume.
That problem led to a cubic equation.