History of trigonometry

Early study of triangles can be traced to Egyptian mathematics (Rhind Mathematical Papyrus) and Babylonian mathematics during the 2nd millennium BC. Systematic study of trigonometric functions began in Hellenistic mathematics, reaching India as part of Hellenistic astronomy. In Indian astronomy, the study of trigonometric functions flourished in the Gupta period, especially due to Aryabhata (6th century AD), who discovered the sine function, cosine function, and versine function. During the Middle Ages, the study of trigonometry continued in Islamic mathematics, building on earlier foundations from Indian (notably Aryabhata's sine and cosine concepts) and Greek (Hipparchus' chord table) sources.

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