Great thinkers whose work has helped shaped today's world.

Ptolemy

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Ptolemy was a great mathematician from ancient Greece who made significant contributions to the field of mathematics. One of his most famous works is the Almagest, a mathematical and astronomical treatise that presented a comprehensive model of the solar system. Ptolemy's model proposed that the Earth was at the center of the universe, with all celestial bodies revolving around it in circular orbits. This geocentric theory greatly influenced early astronomy and was widely accepted for centuries.

Students studying mathematics may also learn about Ptolemy's work in trigonometry. He developed tables of chords, which are equivalent to modern trigonometric tables, to aid in the calculation of angles and distances in astronomy and geography. These tables helped astronomers make accurate measurements of celestial objects and navigate the seas.

Have you heard of Ptolemy's Theorem? It states that in a cyclic quadrilateral (ABCD), the sum of the products of its two pairs of opposite sides is equal to the product of its diagonals.

The formula is expressed as:

AC × BD = AB × CD + AD × BC

Overall, Ptolemy's contributions to mathematics and astronomy laid the foundation for further advancements in these fields and continue to be studied and appreciated today."

Print this large QR code and display it on your classroom's History of Mathematics timeline. When people scan the code with their phones, they'll be directed to this page about Ptolemy.