Hipparchus trigonometry and chord table
Trigonometría y tabla de cuerdas de Hiparco
- Date
- c. 150 BCE · confidence medium
- Place
- Rhodes, Greece
- Credited to
- Hipparchus of Nicaea
- People
- 👤 Hiparco de Nicea190 BCE–120 BCE
- Field
- Knowledge & symbols
What was discovered
First table of chords as a function of angle, with which he solved triangles to predict astronomical positions and discovered the precession of the equinoxes. It is the birth of trigonometry.
The 360 degrees of the circle entered Greek mathematics through Hipparchus.
What it led to
- Ptolemy's Almagest
- Indian trigonometry (the sine)
- spherical trigonometry
Built on
- Euclidean axiomatic geometryc. 300 BCE
- Euclidean geometry
- base-60 Babylonian astronomy
Made possible
- Almagest and Ptolemy theoremc. 150 CE
- Early planispheric astrolabec. 150 CE
- cartography
- navigation