Direct deduction is direct analysis deduction. Direct deduction is based on conditions, using relevant knowledge to directly analyze, deduce or calculate the results, so as to make correct judgments and choices. This method is generally used to calculate multiple-choice questions and is also commonly used in other types of questions. This is the most basic, commonly used and important method.

Method 2: Reverse deduction

Reverse deduction is reverse deduction or reverse substitution. The reverse deduction method is to use options (that is, multiple-choice options) to reverse the conditions, eliminate the options that contradict the conditions, and the ones that meet the conditions are the correct ones, or substitute one or several options in turn into the topic setting conditions for verification and analysis, and the ones that meet the topic setting conditions are the correct ones.

Method 3: reduce to absurdity

Among the four options of multiple-choice questions, if one option is assumed to be incorrect (or correct) and contradictions can be deduced, it means that the option is correct (or incorrect). When choosing which option to start with, you must analyze and judge according to the conditions of the topic, and sometimes you may need some intuition.

Method 4: Counterexample method

If an option is a proposition, to exclude it or explain that the proposition is wrong, sometimes just give a counterexample. Counterexamples are usually some commonly used, simple but illustrative examples. If we pay due attention to accumulating different counterexamples related to various knowledge points when reviewing or doing problems, it may come in handy in the exam.

Method 5: Special case method (special value method)

If the topic is a universal proposition, you can try to take one or several special situations and special values to verify which options are correct and which are wrong, or which options are likely to be correct or wrong, so as to make the right choice.

The special case method is particularly effective in the following situations: (1) When the conditions and conclusions are universal, certain options are determined or excluded by taking special cases; (2) When the conclusion that cannot be established or most likely cannot be established needs to be proved wrong by giving counterexamples; (3) For some problems that are difficult to judge, assume that it is correct under special circumstances.

Method 6: Number-shape combination method

Draw the corresponding geometric figures according to the conditions, and analyze them by combining mathematical expressions and figures, so as to make correct judgments and choices. This method is often used in multiple-choice questions related to geometric figures, such as: geometric meaning of definite integral, calculation of double integral, curve and surface integral, etc.

Method 7: Exclusion method

If three of the four options can be excluded by one or more methods, then the remaining one is of course the correct option, or two of the four options can be excluded first, and then the remaining two can be judged.

Method 8: Intuition method

If you can't make a choice by the above methods, make a choice by intuition or first impression. Although intuition is not very reliable, it can be used as a reference, and people's intuition or first impression sometimes plays a role.

What are the solutions to multiple-choice questions in mathematics for postgraduate entrance examination? Bian Xiao stops here. More questions about admission, registration time, result inquiry, registration fee, admission, printing time of entrance examination admission ticket will be updated in time. I hope all candidates can be admitted to their ideal institutions. Everyone should master the skills of preparing for the exam.