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The first table compiled on trigonometric values of arc and chord for a series of angle measurements was created by Hipparchus of Nicaea
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AD
Ptolemy expanded on Hipparchus's work and created a table of his own on chord values. He also develeoped the first evidence of several trigonometric identities in his Almagest, such as the half-angle formula, and the sum and difference formulas of sine and cosine. -
BCE.
The first table compiled on trigonometric values of arc and chord for a series of angle measurements was created by Hipparchus of Nicaea -
Aryabhata, an Indian mathematician and astronomer, expanded on the works of the Siddhantas and created many sine and cosine tables. He published these works in the Aryabhatiya.
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AD
Major developments are made in India in the fifth and sixth centuries by the five Siddhantas (Indian philosophies), which outlined the conventions of trigonometric ratios and how they are used in astronomical observations. -
AD
Muhammad ibn Mūsā al-Khwārizmī develops the first table of tangents of certain measures of angles. -
AD
Habash al-Hasib al-Marwazi developes the first table of cotangent values of certain angle measurements. -
AD
Muhammad ibn Jābir al-Harrānī al-Battānī developes the first tables of the reciprocal functions secant and cosecant for certain angle measures. -
AD
Abū al-Wafā' al-Būzjānī, a Persian mathematician is using all six trigonometric functions, and developes the Law of Sines for spherical trigonometry. -
AD
Bhaskara II, an Indian mathematician of the 12th century, was the first to develope the formulas
sin(a+b)=sin(a)cos(b)+cos(a)sin(b)
sin(a-b)=sin(a)cos(b)-cos(a)sin(b) -
AD
The indian mathematician uses what will become to be known as Taylor series expansions to produce the values of trigonometric functions with a new record of accuracy. He also developed expansion series for pi. -
After trigonometry finally makes its way to Western Europe, Georg Joachim Rheticus, a student of Copernicus, is the first to define all six trigonometric functions in terms of right triangles in his work, The Opus palatinum de triangulis.
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Euler's famous identity is published.
e ^ (ix) = cos (x) + isin (x)