1, can you specifically ask, is it possible that the number four is a professional graduate student? If you are not a professional graduate student, it may be that your research direction doesn't need too many mathematical applications during your graduate study.

2. Graduate students are divided into professional graduate students and academic graduate students. If you choose the number four as a professional graduate student, then I suggest you choose the number three. Professional graduate students used to only recruit students for social workers. Only in the past two years have we started to recruit fresh undergraduates, and the social recognition of professional postgraduates is not as good as that of academic postgraduates. If you are also an academic graduate student, it will not affect your postgraduate entrance examination. It should be easier to review the number four than the number three.

3. Non-mathematics majors in universities mainly do more questions, remember questions and remember examples, which is the best way. There is no shortcut to math learning, but you can't die. Do two or three questions for one question, and remember that the method is the key.