1, ∞ infinity.

2.ππ。

3. The absolute value of | x |.

4.∪ Union.

5, ∩ intersection.

6.≥ greater than or equal to.

7, less than or equal to.

8.≡ Constant is equal to or congruent.

9.ln(x) is a logarithm based on e.

9. lg(x) logarithm based on 10.

Integer functions on 10 and floor (x).

Integer functions under 1 1 and ceil(x).

12, x mod y is the remainder.

13, x-floor(x) fractional part.

14, ∫f(x)dx indefinite integral.

Mathematics learning methods in senior high school:

1, proficient in textbook knowledge

Learning high school mathematics must be proficient in textbook knowledge. For example, the formula derivation of trigonometric function in senior one and the length calculation of line segment in senior two solid geometry have to go through complicated derivation. If you don't master the textbook knowledge, you can't just remember the formula, apply the formula and change the topic slightly. The fundamental reason is that the knowledge points of textbooks are not thoroughly mastered.

To master textbook knowledge, we must preview textbook knowledge, listen carefully to the teacher explain textbook knowledge in class, ask questions if you don't understand, review after class, and if you still don't understand after review, it means you don't understand in class. Understand what you don't understand in time.

2. Think more.

When previewing knowledge before class, we must think about the knowledge in the textbook and understand the definitions and theorems in the textbook. Theorem proof and formula derivation in textbooks must be done by yourself. If you can't do it, don't read the textbook, think for yourself. Only what you think is the most precious.

When you meet something you don't understand, don't always think about asking, think about it first. It is the same to do the problem. Don't look at the answer directly, think with your head. If you really can't think of it, just look at the answer or ask the teacher for ideas.

3. Do more math exercises.

Some students just read books, and they have a good knowledge of textbooks and can generalize the contents of books, which is good, but there is still a gap between mastering knowledge and getting high marks in exams. The content of the textbook is common sense, but it is not comprehensive enough. Mastering textbook knowledge is helpful to solve difficult problems, but it does not mean that it can solve difficult problems.

As a high school student, when buying an extracurricular exercise book, you can buy a pure reference book for solving problems or a reference book with exercises and detailed answers. The exam outline is in the textbook, but the exam topics may be ever-changing. It is necessary to increase the understanding of the knowledge points in the textbook through practice and understand the knowledge points more comprehensively through doing the questions.