What r some interesting facts about Ptolemy that can be made into a paragraph?
Claudius Ptolemy (85-165 AD) wrote “Almagest” (13 Books) giving the mathematics for the geocentric theory of planetary motion. Considered a masterpiece with few peers, Almagest remained the major work in astronomy for 1400 years until it was superceded by the heliocentric theory of Copernicus. Nevertheless, in Books 1 and 2, Ptolemy refined the foundations of trigonometry based on the chords of a circle established by Hipparchus. One infamous result that he used, known as “Ptolemy’s Theorem”, states that for a quadrilateral inscribed in a circle, the product of its diagonals is equal to the sum of the products of its opposite sides. From this, he derived the (chord) formulas for sin(a+b), sin(a-b), and sin(a/2), and used these to compute detailed trigonometric tables Ptolemy (aka Claudius Ptolemaeus, Ptolomaeus, Klaudios Ptolemaios, Ptolemeus) lived in Alexandria (in Egypt) from approx. 87 -150 AD. Very little is known about his personal life (the image above is probably purely the art
