Mathematical method function method, which is to convert some calculations into functions, first bring in the answers, then shift the terms to turn one side of the equation into zero, and then you can roughly draw the expression of the function to see if there is a unique focus and zero, so that you can roughly judge the answers or find the answers closest to zero!
Empirical method: it is also used in sorting or conventional topics. First, for example, find the triangle area. Look at the answers A: 12, B: 13, C: 6, D: 1 1. First, 12, 13, 1 1 are obviously the wrong answers. Secondly, there must be a trap of forgetting to divide the triangle area by 2, so the correct rate of C's answer is high. There are some answers, and the first few are repeated, just like the picture below, so we won't just choose to repeat more answers! 1 2 There are two duplicate answers, and C and D are the most likely.
If, really can't find any method, then look at the answer, there are * * * common divisors generally have the correct answer. Generally, those answers will not have similar answers to the other three, but they are generally wrong. It can be ruled out directly, and finding the answer is actually finding the difference. Look through the author's thoughts, consider what trap the topic wants to set, and eliminate some irrelevant answers.
Methods of solving different problems in mathematics 1. Constant establishment problem
The problem of constant establishment or its opposite can be transformed into a maximum problem. Pay attention to the application of quadratic function, and flexibly use the maximum value on closed interval and the idea of classification discussion. Classification discussion should not be repeated or omitted.
2. Conic curve problem
The topic of conic curve must be defined first. For the problem that a straight line intersects a conic curve, if it is related to the midpoint of the chord, the method of setting instead of finding the point difference is chosen, and if it is not related to the midpoint of the chord, the method of Vieta theorem formula is chosen; When using Vieta theorem, we should first consider whether it is the discriminant of quadratic sum root;
3. Curve equation
To solve the curve equation, if you know the shape of the curve, you can choose the undetermined coefficient method. If you don't know the shape of the curve, the steps are to establish the system, set points, formulate and simplify (pay attention to remove the special points that don't meet the conditions);
4. Centrifugal rate
Find the eccentricity of ellipse or hyperbola, and establish the relationship equation of A, B and C;
5. Trigonometric function
Trigonometric function is to find the period, monotonous interval or maximum value, which is converted into chord function with the same angle first, and then solved by auxiliary angle formula. To solve the triangle problem, pay attention to the use of internal angle sum theorem; For vector-related topics, pay attention to the range of vector angles;