"The Hindus were not so successful in geometry. In the measurement and construction of altars the priests formulated the ... several hundred years before the birth of Christ. Aryabhata, probably influenced by the Greeks, found the area of a triangle, a trapezium and a circle, and calculated the value of π... at 3.1416—a figure not equaled in accuracy until the days of Purbach... Bhaskara crudely anticipated the differential calculus, Aryabhata drew up a table of sines, and the ' provided a system of trigonometry more advanced than anything known to the Greeks."