Textbooks just let you know the role of this knowledge. To use book knowledge flexibly, you need a lot of questions and summaries. It is impossible to get everything done just by reading a few times!
At present, there are many tutorials used in China, one is People's Education Press, and the other is East China Normal University Press. They are not very detailed, but all the knowledge points can be included, mainly a flexible process!
Extracurricular books play a role in perfecting textbooks and supplementing knowledge.
If you want to learn mathematics well, you must first read through the textbook, understand the derivation and source of the formula, and use it flexibly with the help of extracurricular books! !