The direct method starts directly from the topic setting, grasps the characteristics of the proposition, and uses definitions, properties, theorems, formulas, etc. And after deformation, reasoning, calculation,

Direct method is a common method to solve fill-in-the-blank problems. When using direct method to solve multiple-choice questions, you can use options to judge.

When calculating and demonstrating, we should pay attention to simplifying the steps as much as possible, jumping reasonably, and making full use of some common properties and typical knots.

Theory, in order to improve the speed of solving problems

2. Equivalent transformation method

Equivalent transformation method is to transform an unknown problem into a problem that can be solved within the scope of known knowledge. Through continuous transformation, unfamiliar, irregular and complex problems are transformed into familiar, standardized and simple problems. In the process of transformation, we must pay attention to the equivalence before and after transformation. When solving multiple-choice questions, the inequality situation is often the place where the options are trapped. When solving the fill-in-the-blank problem, there will be inequality, and there will often be missing or multiple solutions.

3. Special value method

When solving multiple-choice questions and fill-in-the-blank questions, you can choose one.

(or some) special value (or special position, special function, special point, special

Equations, special sequences, special graphs, etc. ), this method is called special value method. Because the special value method only needs to test special values and special situations, it saves the time of reasoning and complicated calculation and improves the speed of solving problems. Special value method is often used to answer multiple-choice questions and fill-in-the-blank questions in exams, and it can play a role of "four or two" if used properly.