Brahmagupta

Brahmagupta (c. 598 – c. 668 CE) was an Indian mathematician and astronomer who is credited as the first person to understand and formalize the concept of the number zero for nothing in mathematics. He is the author of two early works on mathematics and astronomy: the Brāhmasphuṭasiddhānta (BSS, "correctly established doctrine of Brahma", dated 628), a theoretical treatise, and the Khandakhadyaka ("edible bite", dated 665), a more practical text. He was the first Indian scholar to describe gravity as an attractive force, and used the term "gurutvākarṣaṇam" in Sanskrit to describe it. He is also credited with the first clear description of the quadratic formula (the solution of the quadratic equation) in his main work, the Brāhma-sphuṭa-siddhānta.