**Brahmagupta** was born in 598. He was a mathematician and astronomer from Central India who demonstrated the general solution to the integer quadratic equation (the diophantines) and developed general algebraic methods for application in astronomy in his major work, * Brahmasphutasidanta* (650).

In your book, * Brahmasphutasidanta*, elevates zero to the category of * samkhya* (that is, from numbers) when giving the first rules for calculating with zero: a number multiplied by zero results in zero; the sum and difference of a number with zero results in this number; etc.

Among his discoveries is the natural generalization of Heron's formula for the cyclic quadrangles, so important, that it is regarded as the most remarkable discovery of Hindu geometry by Brahmagupta.

He wrote a book in verse on astronomy, with two chapters on mathematics: arithmetic progression (with which he found the sum of the series of natural numbers), equations of the second degree, and geometry (with which he found the areas of triangles, quads, and circles). as well as volumes and side surfaces of pyramids and cones). In this book, there is the negation of the rotation of the earth.

Arabic Numerals - The numerical symbols 1, 2, 3, 4, 5, 6, 7, 8, 9, the numerals, were invented by the Hindus around the 5th century AD for a base numbering system 10 with notation. positional. The use of zero by Hindus is recorded in the seventh century in Brahmasphutasidanta (The Opening of the Universe) written by Brahmagupta.

The number system of the Hindus is disclosed by the book "About the Indian Art of Calculating", written in 825 by the Persian mathematician and astronomer al-Kwarizmi (origin of the words digit and algorithm). Al-Kwarizmi's work arrives in Islamized Spain in the tenth century. Hindu numerical symbols are adopted by Italian traders and spread throughout Europe. They are called Arabic numerals in contrast to the Roman numerical system, still used at the time.