The mathematician who first framed the rules of operation for zero was Brahmagupta. He was also to give a solution to indeterminate equations of the type ax2 + 1 = y2 and the founder of a branch of higher mathematics called “Numerical analysis". No wonder Bhaskara, the great mathematician, conferred on him the title of Ganakachakrachudamani, the gem of the circle of mathematicians.
Brahmagupta was born at Bhillamala (Bhinmal), in Gujarat, in 598 A.D. He became court astronomer to King Vyaghramukha of the Chapa dynasty. Of his two treatises, Brahmasphutasiddhanta and Karanakhandakhadyaka, the first is the more famous. It was a corrected version of the old astronomical text, Brahmasiddhanta. It was translated into Arabic, but erroneously titled Sind Hind. For several centuries the treatise remained a standard work of reference in India and the Arab countries.
Brahmasphutasiddhanta also contains chapters on arithmetic and algebra. Brahmagupta’s major contribution is the rules of operation for zero. He declared that addition or subtraction of zero to or from any quantity, negative or positive, does not affect it. He also added that the product of any quantity by zero is zero and division of any quantity by zero is infinity. He, however, wrongly claimed that division of zero by zero was zero.
He also framed rules to solve a simple equation of the type ax + b = 0 and a quadratic equation of the type ax2 + bx + c = 0, as well as methods to sum up a geometric series. Besides, he noted the difference between algebra and arithmetic and so was the first mathematician to treat them as two separate branches of mathematics.
Brahmagupta’s Karanakhandakhadyaka is a hand-book on astronomical calculations. In this he effectively used algebra for the first time in calculations. But Brahmagupta always was careful not to anger the priests. His wives were orthodox, in keeping with the beliefs held during those times, and he criticized Aryabhata, who said the earth was not stationary. But he believed that the earth was round.
About gravity he said: “Bodies fall towards the Earth".