A great mathematician Qin (1202 ~ 126 1) appeared in the Southern Song Dynasty. Qin was born in Sichuan and later moved to Hangzhou, the capital of the Southern Song Dynasty. Besides the ancient mathematical heritage, Qin often "accepted mathematics from hermits", including China folk mathematicians and many Arab scholars and businessmen living in Hangzhou. He wrote "Nine Chapters of Mathematics" and created a method to find the positive roots of mathematical equations. In Qin's view, mathematics is "big enough to understand the gods and follow their lives; If you are small, you can help the world, such as everything "(Introduction to Nine Chapters of Mathematics).
Yang Hui, a native of Hangzhou, is younger than Qin and a famous mathematician in the Southern Song Dynasty.