Zhu Shijie

Zhu Shijie, also written Chu Shih-Chieh, was a Chinese mathematician of the thirteenth and fourteenth centuries, born at Yanshan near present-day Beijing. Very little is recorded about his life beyond a preface saying that he travelled widely for more than twenty years and taught a growing number of pupils, and that he wrote two books. The Suanxue qimeng, an introduction to mathematical studies published in 1299, was aimed at beginners, covered fractions, decimals and the rule of false double position, and later served as a textbook in Korea and Japan. The Siyuan yujian, the Jade Mirror of the Four Unknowns, published in 1303, extended the method of the celestial unknown to polynomials in up to four unknowns. It opens with a diagram of the binomial coefficient triangle up to the eighth power, presents 288 problems, and marks the peak of Chinese mathematics of its period. Its text was lost for a time and later recovered in a corrupted copy, so the surviving version is not exactly the one Zhu published.