The distribution function is right continuous, and the general equal sign should be considered on the left. The density function doesn't matter, the equal sign can be added or not, and generally it doesn't need to be added. If added, it should be consistent with the distribution function.

Cumulative distribution function is an important function in probability statistics. It is through it that random variables can be studied by mathematical analysis.

Distribution function is the most important probability feature of random variables, which can completely describe the statistical law of random variables and determine all other probability features of random variables.

Tips for learning mathematics

1, you should be good at thinking when learning mathematics, and the answers you come up with are far more impressive than those others say.

2. Do a good preview before class, so that we can better digest and absorb the unknown knowledge points in math class.

3, the mathematical formula must be memorized, and it must be deduced and can be deduced.

4. The most basic thing to learn mathematics well is to master the knowledge points of textbooks and exercises after class.

5. 80% of the scores in mathematics come from the basic knowledge, and 20% of the scores are difficult, so it is not difficult to test 120.