Postgraduate entrance examination videos are of little use, and mathematics depends on your own understanding. Especially linear algebra, linear algebra must be understood thoroughly, otherwise even if you recite the formula, sometimes you can't even understand the questions. There is still plenty of time. Go through the knowledge points first, then consolidate the topic, and recite more common formulas on the basis of understanding. Line generation has a characteristic, some problems are just a solution, you either do it or don't do it; Although there are many solutions to some problems, it will take you 15 minutes to work them out, and others may work them out in 5 minutes by simple methods. So be sure to understand it thoroughly.

As for reference books, I suggest buying one from Li Yongle. Chen Wendeng's line generation is inferior to his. The knowledge points and difficulties in it are well summarized. It is estimated that it will be done at most 1 month. Don't forget that math 1 is easy to test high numbers and probabilities, and you can't lose sight of one thing and lose sight of another.

Good luck ~