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.
- Born: about 220 or 225 in Wei, China
- Died: about 280 or 295 in China
Theorems and Definitions
- 263: Commentary on the Chiu Chang Suann Jing ("Nine Chapters on the Mathematical Art")
- 263: Haidao Suanjing ("The Sea Island Mathematical Manual")