he was the first to recognize fractions as numbers.

His book “Sphaerica” dealt with the geometry of the sphere and its application in astronomical measurement and calculations.

He is best known as an engineer and inventor, and now considered of one of the greatest pure mathematicians of all time.

he was perhaps the greatest of all ancient astronomers. He calculated (with remarkable accuracy for the time) the distance of the moon from the earth by measuring the different parts of the moon using the properties of triangles.

He introduce the concept of spherical triangle (a figure formed of three great arcs, which named “trilaterals”

He is considered an early innovator of algebra, and applied quite complex algebraic problems.

He also discovered on computing square roots, in fact he is a mathematician to confront at least the idea of √(−1).

he was the first to recognize geodesics on a curved surface as a natural analogues of straight lines on a flat plane.

As a mathematician, his greatest legacy is the “Sieve” algorithm of identifying prime numbers.

He calculated the circumference of the earth to a remarkable degree of accuracy.

he is a mathematician, astronomer and geographer.

are collections of problems with numerical solutions.

he work on geometry particularly in conics and conic sections (circle, parabola, ellipse, and hyperbola) and showed how they could be derived from different sections through a cone.

He has the most prominent work on Algebra in all Greek mathematics and his problems exercise the minds of many of the world’s best mathematicians.

he is best known in mathematical circle for triangle with integer sides and integer area.

he spent most of his life in Syracuse, Sicily.

Father of Geometry

He devised the first system of latitude and longitude.

h was a great chronicler of the mathematics of the time, and one of the most influential teacher in history.

He produces his work “Almagest” a table of trigonometric chords in a circle for steps of ¼ degree.