First, the substitution method
There are two main alternatives. One is to appear in multiple-choice questions, that is, to directly bring the answer options of the questions into the questions for verification, which is also a relatively fast method. The other is to find the symmetric function of a known function about a point or a straight line, and bring the expression of the function or the nature of the function into it to solve the problem directly, which is usually suitable for filling in the blanks, and the difficulty is not too great.
Second, the monotonicity method
Monotonicity is a common and efficient method to solve functions. Monotonicity of function is a particularly important property of function, and it is also the focus of college entrance examination every year. However, due to the lack of understanding of basic concepts and unclear examination questions, many students are prone to make wrong solutions when answering such questions. The following are the matters needing attention in doing this kind of problems, so as to attract the attention of students.
Third, the undetermined coefficient method
The key to solve the problem by undetermined coefficient method is to list the equality or equation correctly according to the functional relationship between known variables. Using the undetermined coefficient method is to determine these unknown coefficients according to the given conditions. Judging whether a problem is solved by the method of undetermined coefficient mainly depends on whether the solved mathematical problem has a certain mathematical expression, and if so, it can be solved by the method of undetermined coefficient.
The basic steps to solve the function problem with the undetermined coefficient method are: 1 First, determine the analytical formula of the undetermined coefficient problem; 2. According to the condition of identity in the topic, list a group of equations with undetermined coefficients; 3. Solve the equation or eliminate the undetermined coefficient by using the basic properties of the function, thus solving the problem.
Fourth, alternative methods.
Method of substitution is mainly used to solve complex function problems. The form of small function expression expressed by variables is called substitution method. Solving a problem with method of substitution can reduce the difficulty of the problem and facilitate observation and understanding.
V. Structural Equation Method
No matter what kind of function is dead, the equation of the function can undoubtedly reduce the difficulty of solving problems, so the equation of the constructor is also a commonly used problem-solving skill, especially in the finale of the college entrance examination, the constructor can also get high marks, so everyone must pay attention to the skill of the constructor method.