Chapter 9 What is an ancient arithmetic book?

It's the book Nine Chapters of Arithmetic. The source of this sentence is a chapter on the miscellaneous problems of equations in China's classical mathematical work "Nine Chapters of Arithmetic". The original text is that its number is not intuitive, its shape is less, and it is difficult to be nuanced; If the number is small and there are many shapes, it is difficult to prepare its side. This chapter mainly talks about the solution methods and ideas of various equation problems that have an important influence on the development of ancient arithmetic. Nine Chapters Arithmetic is one of China's earliest works devoted to the study of ancient mathematics, and is usually called the first of the three ancient arithmetics. The book records a wealth of mathematical content, including arithmetic, algebra, geometry, number theory and other fields.