Mathematical analysis uses limit tools to study the properties of functions, such as continuity, differentiability and integrability. He is also the basis for future study, such as the theory of real variable function, and mathematical analysis is a special case of real variable function theory in some cases. Therefore, you must first learn the limit. The teaching materials of mathematical analysis generally start from the limit, and the midpoint here is ε -δ language and Cauchy convergence criterion, etc ... The latter limits are not difficult to learn, and they are all described in the limit language. Secondly, how a person's analytical ability determines his grasp of the truth. Once the analysis is not good, the true letter can be declared dead. Of course, to tell the truth, there is no way to learn mathematics, that is, to do problems, and to quote Zhou Minqiang, the real superman of Peking University, in his Mathematical Analysis Exercise that "skill is more important than practice, and cleverness is more important than understanding". Here are some teaching materials for mathematical analysis: Zhang Zhusheng's New Theory of Mathematical Analysis, Zhuo Liqi's Mathematical Analysis and Tao Zhexuan's Real Analysis of Tao Zhexuan (this book can also be used as a teaching material for real change). The textbooks of China Normal University are really rubbish and will only mislead other people's children. I recommend several sets of mathematical analysis exercises: Zhou Minqiang's mathematical analysis exercises mentioned above, Pei's Typical Problems and Methods in Mathematical Analysis, and of course Pei's Sunflower Collection of Mathematical Analysis are also very good. As for Shi Huaiji's books from China University of Science and Technology, all books in Jilin are rubbish ... Again, if you don't learn mathematical analysis well, it means that you will be scrapped in the future.