Aryabhata

Aryabhata was the first of the major mathematician-astronomers from the classical age of Indian mathematics and Indian astronomy. His works include the Āryabhaṭīya (499 CE, when he was 23 years old) and the Arya-siddhanta. and the Arya-siddhanta. Aryabhata called himself a native of Kusumapura or Pataliputra (present day Patna, Bihar). Aryabhata is the author of several treatises on mathematics and astronomy, some of which are lost.
His major work, Aryabhatiya, a compendium of mathematics and astronomy, was extensively referred to in the Indian mathematical literature and has survived to modern times. The mathematical part of the Aryabhatiya covers arithmetic, algebra, plane trigonometry, and spherical trigonometry. It also contains continued fractions, quadratic equations, sums-of-power series, and a table of sines.
The place-value system, first seen in the 3rd-century Bakhshali Manuscript, was clearly in place in his work. While he did not use a symbol for zero, the French mathematician Georges Ifrah argues that knowledge of zero was implicit in Aryabhata's place-value system as a place holder for the powers of ten with null coefficients. Aryabhata worked on the approximation for pi ( {\displaystyle \pi } \pi ), and may have come to the conclusion that {\displaystyle \pi } \pi is irrational.
His death was 550 CE.