1. According to the inquiry of Senior Three Network, compulsory mathematics in senior high school is the first teaching auxiliary material required in the learning order of senior high school mathematics.

2. The main content of "Compulsory Mathematics for Senior High School II" is to understand spatial graphics, and to cultivate and develop spatial imagination through the overall grasp of spatial geometry.

3. The main content of compulsory mathematics in senior high school is to explain and summarize the knowledge of algorithm, statistics and probability.

4. The compulsory mathematics content of senior four includes trigonometric function, plane vector and trigonometric identity transformation. Trigonometric function is an important mathematical model to describe periodic phenomena and plays an important role in mathematics and other fields. This is the last basic elementary function that students study in senior high school.