Nine chapters of arithmetic
2 min readZhoubi Suanjing（The Arithmetical Classic of the Gnomon and the Circular Paths of Heaven）was essentially an astronomy text，thought to have been compiled in the lst century BC or earlier，containing some important mathematical sections.
This book measures the positions of the heavenly bodies using shadow gauges，which are also called gnomons. How a gnomon might be used is described in a conversation in the text.Zhoubi Suanjing contains calculations of the movement of the sun through the year as well as observations of the moon and stars，particularly the pole star.Perhaps the most important achievement included in this book is the Gougu Rule，which is the Chinese version of the Pythagorean Theorem. The text of Zhoubi Suanjing also explains that mathematics can be applied to many different cases and that mathematical reasoning allows one to pass from particular to general situations.This realization of the abstract nature of mathematics is important.
Jiuzhang Suanshu，The Nine Chapters on the Mathematical Art）is another important Chinese mathematical book.The book is broken up into nine chapters containing 246 questions with their solutions and procedures.Each chapter deals with specific field of questions.The book was co-compiled by several people and finished in the early Eastern Han Dynasty（about the lst century），indicating the formation of the ancient Chinese mathematical system.
It became the criterion of mathematical learning and research for later generations and was annotated by many mathematicians.Among them were Liu Hui（born around 250）and Li Chunfeng（602-670），who annotated the book in 263 and 656 respectively.Thebook was introduced to Korea and Japan during the Sui and Tang Dynasties.Now，it has been translated into several languages，including Japanese，Russian，German，English and French.
