Abstract method is to extract the main points of knowledge and sort out the review. First, write out the original question for later thinking. Then the specific problems are analyzed in detail, and the causes of the errors are analyzed, so as to deepen understanding. Secondly, there must be standardized steps in writing positive solutions. At the same time, the type must be clear, and finally draw inferences. Finally, if conditions permit, write the wrong questions and class questions on the front of the notebook, write the reasons and positive solutions of the wrong questions on the back, extract the good questions, and copy the questions and answers of typical problems encountered in the study in the notebook for further study.

The process of extracting conditions is a process of mathematical modeling. By effectively combining the conditions, the problem is attributed to the existing problem-solving experience, so as to formulate and implement the problem-solving plan. Good problem-solving ideas come from past experience and acquired knowledge, and extraction conditions support good problem-solving ideas.