Zhu Shijie

Two of his mathematical works have survived: Introduction to Computational Studies (算學啓蒙 Suan hsüeh Ch'i-mong) and Jade Mirror of the Four Unknowns.

The book was once lost in China, until the Qing dynasty mathematician Luo Shilin bought a Korean printed edition and republished it in Yangzhou.

Zhu's second book, Jade Mirror of the Four Unknowns (1303) is his most important work, advancing Chinese algebra.

He then solves the high order equation by "Ling long kai fang" method of Southern Song dynasty mathematician Qin Jiushao (from Shùshū Jiǔzhāng, “Mathematical Treatise in Nine Sections” of 1247).

Zhu also found square and cube roots by solving quadratic and cubic equations, and added to the understanding of series and progressions, classifying them according to the coefficients of the Pascal triangle.

SIYUAN YUJIAN PDF-036-036
Suanxue qimeng
Illustrations in Jade Mirror of the Four Unknowns