First, the trigonometric function problem pays attention to the correctness of the normalization formula and the induction formula (when it is converted into a trigonometric function with the same name and the same angle, the normalization formula and the induction formula (singular change, even constant; When symbols look at quadrants, it is easy to make mistakes because of carelessness. One false move may lose the game. )。 Second, the sequence problem 1, when proving that a sequence is an arithmetic (proportional) sequence, at the end of the conclusion, you should write the arithmetic (proportional) sequence, who is the first item and who is the tolerance (common ratio); 2. When the last question proves the inequality, if one end is a constant and the other end is a formula containing n, the scaling method is generally considered; If both ends are formulas containing n, mathematical induction is generally considered (when using mathematical induction, when n=k+ 1, the assumption when n=k must be used, otherwise it is incorrect. After using the above assumptions, it is difficult to convert the current formula into the target formula, and generally it will be scaled appropriately. The concise method is to subtract the target formula from the current formula and look at the symbols to get the target formula. When drawing a conclusion, you must write a summary: it is proved by ① ②; 3. When proving inequality, it is sometimes very simple to construct a function and use the monotonicity of the function (so it is necessary to have the consciousness of constructing a function). Third, the solid geometry problem 1, which proves the positional relationship between a straight line and a plane, generally does not need to be established, and it is relatively easy; 2. It is best to establish a system when solving the problems such as the angle formed by straight lines on different planes, the included angle between lines and planes, the dihedral angle, the existence problem, the height, surface area and volume of geometry. 3. Pay attention to the relationship between the cosine value (range) of the angle formed by the vector and the cosine value (range) of the angle (symbol problem, obtuse angle problem, acute angle problem). For more relevant knowledge, you can also pay attention to the mathematics curriculum of Beijing New Oriental High School.