Ye Li 1
Ye Li (1192-1279), formerly known as Li Zhi, whose real name is Jingzhai. He was born in Luancheng (now Luancheng District, Shijiazhuang City, Hebei Province). Mathematicians in the Jin and Yuan Dynasties. At the end of Jin Zhengda, he became a scholar and discovered Zhou Jun. Ye Li's main contribution to mathematics is astrophysics (the method of setting unknown parallel equations), which is used to study the properties of inscribed circle and circumscribed circle of right triangle. Together with Yang Hui, Qin and Zhu Shijie, they are also called "the four great mathematicians of Song and Yuan Dynasties".
2. Yang Hui
Yang Hui, Qian Guang, Han nationality, Qiantang (now Hangzhou, Zhejiang Province) was an outstanding mathematician in the Southern Song Dynasty. He used to be a local administrative officer in the Southern Song Dynasty, and his footprints were all over Suzhou and Hangzhou. He has made great contributions to summarizing agile algorithms such as folk multiplication, division, "superposition", vertical and horizontal diagrams, and mathematics education. He is the first mathematician in the world to draw a rich vertical and horizontal map and discuss its composition law. He also proved the sagittal formula, which was called "Shu Hui" at that time.
3. Qin
Qin (1208- 1268), an ancient China native, was born in Zhou Pu (now Anyue County, Sichuan Province), and his ancestral home was Army County. He studies astrology, rhythm, arithmetic, poetry, bows, swords and architecture. He served as the magistrate of Qiongzhou and Sinongcheng, and was later demoted and died in Meizhou.
4. Zhu Shijie
Zhu Shijie (1249- 13 14), whose real name is Han Qing, is a native of Songting, Han nationality and Yanshan (now Beijing). Zhu Shijie developed the "Quaternary Technique" on the basis of celestial sphere technique at that time, that is, he listed the polynomial equation of higher degree and its elimination method. In addition, he also created the "superposition method", that is, the summation method of high-order arithmetic progression, and the "trick", that is, the high-order interpolation method.
The influence of celestial magic
The emergence of celestial sphere provides a unified method for equations, and its steps are much more advanced than the algebra of Arab mathematicians. In Europe, this was not achieved until16th century. In addition, the method of addition, multiplication and division, which was founded in the Song Dynasty, simplified the operation process of solving the positive root of mathematical high-order equations. Therefore, in this period, there were simple and clear methods and procedures for solving equations, and China's classical algebra developed to a relatively complete stage.
Moreover, after the celestial sphere technology, mathematicians quickly extended this method to higher-order multivariate equations. For example, Li Dezai's Collection of Talented Persons with Two Instruments has the duality of heaven and earth, Liu Dajian's Gankun Kuobao has the ternary of heaven, earth and people, and finally Zhu Shijie founded the Quaternary Technique.