Answering skills of multiple choice questions in senior high school mathematics
1, direct method
Starting directly from the conditions of the topic, using the knowledge of related concepts, properties, theorems, rules and formulas, through strict reasoning and accurate operation, the correct conclusion can be drawn. Direct method is the most commonly used basic method to solve multiple-choice questions, and low-level multiple-choice questions can be solved quickly by this method. The direct method has a wide range of applications, and as long as the operation is correct, the correct answer will be obtained.
2. Exclusion method
Starting from the conditions of topic setting, this paper deduces by using theorems, properties and formulas, and gradually eliminates the interference term according to the instruction of choosing one from four, so as to get the correct judgment. The screening method is suitable for qualitative or multiple-choice questions that are not easy to solve directly. When there is more than one condition in the topic, first find out the obvious contradiction in the selected branch according to some conditions and deny it, and then find out the contradiction in the narrowed range of selected branches according to other conditions, so as to gradually screen until the correct choice is obtained.
3. Number-shape combination method
According to the conditions of the topic, make the curve or related figure of the studied problem, and make the correct judgment with the intuition of geometric figure. It is customarily called the combination of numbers and shapes. It is very simple and effective in solving multiple choice questions.
4. Valuation method
Because multiple-choice questions provide the only correct choice, and the solution does not need a process, it can be obtained through guessing, reasonable reasoning and estimation. This can often reduce the amount of calculation and naturally strengthen the level of thinking. Estimation saves a lot of derivation and complicated calculation, and saves time, so it is fast. Widely used, it is an important operation method for people to find, study and solve problems.
In fact, the most important thing is substitution. Some options, you just need to bring them in, which is actually very simple.
Expanding reading: problem-solving skills in senior high school mathematics
1, the question type of inequality, equation or function, think directly before establishing the relationship between them. Consider the domain first, and then use the "three-in-one theorem".
2. When learning elementary functions with parameters, we should grasp the characteristics that no matter how the parameters change, some properties remain unchanged. Such as the fixed point of a function, the symmetry axis of a quadratic function, etc.
3. Transcendence appears in the zero-seeking function, and the thinking method of combining numbers and shapes is preferred.
4. In the problem of constant establishment, using the image properties of quadratic function and flexibly applying the idea of maximum value in the closed interval of function and classification discussion (attention should be paid not to repeat or omit in the classification discussion), it can be transformed into a maximum value problem or a constant establishment problem of quadratic function.
5. When choosing to fill in the blanks, the special value method should be preferred.
6. In the problem of finding the maximum value by using the geometric meaning of distance, the shortest line segment between two points should be considered first, and the minimum value of the sum of distances is often found by using quadratic conclusions; The difference between two sides of a triangle is smaller than the third side, which is often used to find the maximum distance difference.