1. Exclusion method: using the information provided in the known conditions and options, three wrong answers are deleted from the four options to achieve the purpose of correct selection. This is a common method. Especially if the answer is numerical, or there is a numerical range, special points can be used instead of verification, thus excluding it.
Next question, y=x is a parity function, y=sin|x| is an even function, and the parity even function is an odd function. Of the four options, only option B is an odd function, so ACD is not included.
2. Special value test method: In the case of ordinary mathematical problems, we can specialize the problems in the process of solving them. The real purpose of eliminating hypocrisy is to use the principle that problems are not facts in some special circumstances and are not facts in general. It is worth noting that the special value method is often used with the exclusion method.
The following questions, the special value of the college entrance examination is 0, and the collocation is clear, except for advertisements; The assignment x=- 1 is obviously inconsistent, and c is excluded.
3. The principle of extremism: analyze the problem that needs to be studied to an extreme state, make the causal relationship clearer, and thus achieve the goal of solving the problem quickly. Most extreme values are suitable for extreme value search, range, analytic geometry and solid geometry. If we analyze many problems with complicated calculation stages and large amount of calculation in an extreme way, the problems can be solved immediately.
Take the extreme case of ABCD directly, import AB focus E, CD focus F, link EF, EFAB and EFCD, and the calculated value is the maximum. Don't need too much explanation.
4. Forward deductive solution: a method of obtaining results through direct calculation and reasoning by using mathematical theorems, formulas, laws, definitions and the meaning of problems. According to the meaning of the following questions, you can substitute the partition function and its inverse function in order.
5. Reverse verification method (inter-question verification method instead of answer): a method of substituting options into questions for verification, thereby denying wrong options and getting correct answers. Always used with exclusion. As shown in the figure below, substituting x=0 is obviously consistent, excluding AD. The assignment x=- 1 is obviously inconsistent, and c is excluded. Choose "B" high school mathematics: master this method of 10, and the high school mathematics multiple-choice questions guarantee that you will not lose a penny.
6. The opposite method: When the previous problem is difficult to solve, gradually find qualified conclusions from the options, or draw conclusions from the opposite side. This method is often used in arranging the combination or probability topics.
7. Number-shape combination method: according to the conditions of the topic, make a graph or image that meets the meaning of the topic, and use the intuition of the graph or image to get the answer through simple reasoning or calculation. The advantage of digital combination is intuitive, and the result can also be measured directly with an angle ruler.
8. Repeated induction: through conditional reasoning, find a way to summarize the correct answer (such as periodic series analysis and other related questions), and often use induction. If you find the following rules, you can analyze the answer.