Zhu Shijie
Zhu Shijie (simplified Chinese: 朱世杰; traditional Chinese: 朱世傑; pinyin: Zhū Shìjié; Wade–Giles: Chu Shih-chieh, 1249–1314), courtesy name Hanqing (漢卿), pseudonym Songting (松庭), was a Chinese mathematician and writer during the Yuan Dynasty. Zhu was born close to today's Beijing. 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.