Textbooks are an essential tool for students to learn and a common thing in life. The cover area of a math textbook is about 5 square decimeters, which is equivalent to the area of a square with a side length of 50 cm (5 decimeters) and a width of 10 cm (1 decimeter).

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200 1 The unified textbooks used in China before were compiled by the Ministry of Education and People's Education Publishing House, and published by People's Education Publishing House, which is common throughout the country. After 200 1 year, the curriculum standards for compulsory education and the curriculum standards for ordinary high schools were issued. Textbooks can be published by various publishing houses and then approved by the Ministry of Education.

According to the users, it can be divided into three categories: primary school textbooks, middle school textbooks and university textbooks. University textbooks are highly professional and have high academic reference value, which are often valued by various libraries.