The combination of numbers and shapes of functions and its application in multiple-choice questions. You can work it out directly without repeating the method.

Sum and general term of sequence: more common in the case of an and Sn appearing at the same time. Solve by direct subtraction.

Solid geometry, naturally, is to find dihedral angle, and the included angle between lines is the key point.

Conic curve is the key and difficult point over the years, which needs special attention. Pay attention to the application of difference method and the calculation of process. But also bound by the problem of calculation range.

Function and derivative: this question is more common in the last big question or the penultimate question (difficult, pay attention to monotonicity and list the answers). Naturally, you can also answer the third question, which will be easier.

Trigonometric function, calculation, need back formula: double angle, half angle, universal, flexible application to get the whole.

Points.

Probability big question (generally the second big question): pay attention to the operation of expectation and variance. I want a list. It is common in practical application problems.