Hello, the process from special to general, and then from general to special is one of the basic processes for people to understand the world. Through the understanding and research of individual cases, the understanding of things is formed, from shallow to deep, from phenomenon to essence, from part to whole, from practice to theory.

For mathematics, the process of studying the basic understanding of mathematical problems from special to general and then from general to special is the special and general idea of mathematical research. In the exam, there are the following types of questions that often use problem-solving methods from special to general:

① Construct a special function

(2) constructing special sequences

③ Looking for special points.

④ Establish special posts.

⑤ Use special values and special equations.

The above situations are all inductive conjecture and analogical conjecture from special to general questions.