Len Berggren - Three geometrical gems from medieval Islamic mathematics

The geometer Abu Sahl Al-Kuhi, who worked in the latter half of the tenth century A.D., excelled in solving problems arising from some of the great traditions of ancient geometry--notably those represented by some of Archimedes works. However, among his extant works are several short ones dealing with problems that do not address any of the famous problems of Greek geometry, but are, nonetheless, intriguing. We shall summarize the contents of these geometrical gems and fit them into the context of the mathematics of the time.