If you have a good understanding, you don't need to take notes, but if necessary, you should take notes: 1. Formula is definitely the first choice, and the best derivation method is also written down. 2. The concept of geometric theorem can also be scribbled, but remember to look at 3. A formula or theorem derived by a teacher from the extension of some content. 4. I won't copy down the examples the teacher told me in class, but I will study them. Sometimes I have to record good memories as bad.