Generally speaking, we have a very accurate grasp of the examination paper of the postgraduate entrance examination mathematics, which is also a major feature of our postgraduate entrance examination mathematics. Although the examination questions change every year, students should be good at discovering trends and laws from changes. This unchangeable rule is the overall requirement of the examination for everyone's knowledge level. Moreover, the knowledge points of our mathematics are often interlocking, one layer contains another layer and permeates each other. If you are in the process of reviewing mathematics, if your knowledge in that field is obviously weak, you are likely to lose the competition and eventually become cannon fodder for the postgraduate entrance examination.

Next, let's look at the systematization of knowledge. The so-called systematization requires candidates to pay attention to the systematization of knowledge in the review process. Here I will give you an example to tell you what is the systematization of knowledge. For example, limit, as we all know, is the most classic and important method to examine limit. In advanced mathematics, there are six calculation methods of limit, namely, four operations of limit, Lobida rule, Taylor formula, logarithmic identity dealing with power function, squeezing theorem and monotone definition. Some students think that just sorting out these things is called sorting out the knowledge system. In fact, what I want to tell you is that it is not enough to just sort out the knowledge system. We should not only do this, but also know the relationship between these six methods. For example, when we get a limit, the first step we should do is to simplify it. We have four limit operations and equivalent infinitesimal substitution. General topics can be worked out through these two steps, but for more complicated topics, after this step, you still need to choose Lobida's law and Taylor's formula. So which method should be used? It needs to be determined according to the characteristics of the topic. Here, my advice to you is that we use the Lobida's law for variable limit functions and Taylor's formula for other cases.