Trigonometry
From Vigyanwiki
Hindu name for the science of Trigonometry is Jyotpatti-ganita or "the science of calculation for the construction of the sine". It is found as early as in the Brāhma-sphuṭa-siddhānta of Brahmagupta (628). In the recent years name appeared as Trikoṇamiti.
The Hindus introduced and employed three trigonometrical functions namely jyā , koṭi-jyā , utkrama-jyā. They are functions of an arc of a circle, but not of an angle.