# Mathematician:Liu Hui

## Mathematician

Chinese mathematician and writer.

Edited and published a book with solutions to mathematical problems presented in Chiu Chang Suann Jing ("Nine Chapters on the Mathematical Art"), in which he gave:

a calculation of $\pi$ (pi) correct to $4$ decimal places
proof of the formulae for the volume of the square pyramid and tetrahedron.

Possibly the first mathematician to discover, understand and use negative numbers.

Chinese

## History

• Born: about 220 or 225 in Wei, China
• Died: about 280 or 295 in China