**Birth:**940

**Death:**997

Great mathematician and astronomer.
Al-Buzjani flourished in Baghdad where he migrated in 959 as a great mathematician - especially in geometry and trigonometry and astronomer - in the field of different movements of the moon, and discovered 'variation'.
Al-Buzjani's contribution in geometry comprises solution of geometrical problems with opening of the compass; construction of a square equivalent to other squares; regular polyhedra; construction of regular hectagon taking for its side half the side of the equilateral triangle inscribed in the same circle and constructions of parabola by points.
Al-Buzjani's contribution to the development of trigonometry was extensive. He was first to show the generality of the sine theorem relative to spherical triangles. He developed a new method of constructing sine tables, the value of sin 30' being correct to the eighth decimal place.
In addition, Abul Wafa or al-Buzjani made a special study of the tangent and calculated a table of tangents. He introduced the secant and cosecant for the first time, knew the relations between the trigonometric lines, which are now used to define them, and undertook extensive studies on conics.
Al-Buzjani wrote a large number of books on mathematics and other subjects including 'Kitab 'illm al-Hisab', a practical book of arithmetic, 'al-Kitab al-Kamil', the Complete Book, 'Kitab al-Handsa' Applied Geometry, books that are extant. He also wrote commentaries on Euclid, Diophantos and al-Khawarizmi.
Al-Buzjani whose full name was Abul Wafa Muhammad Ibn Muhammad Ibn Yahya Ibn Ismail al-Buzjani was born in Buzjan, Nishapur.

Compiled by:*M. Nauman Khan / Ghulam Mohiuddin*