c.1114 - c.1185
Also known as Bhaskara the Learned form Bidar, India, Bhaskara was the leading mathematician of the 12th century. He wrote the first work with systematic use of the decimal number system.
Bhaskara developed rules for equations to calculate trigonometry, and he used letters to represent unknown quantities, much as in modern algebra. As astronomer he popularized the astronomical knowledge of his time.
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From the University of St. Andrews, Scotland
School of Mathematics