大家知道,概率论研究的是随机现象,而要了解随机现象,一是要知道随机现象中所有可能出现的结果,二是要知道每个结果出现的概率.对于给定的随机现象,首先就要描述可能出现的结果,常用的做法是用数字来表示可能出现的结果,将每个结果对应一个数.于是,随机变量这一概念便应运而生:若一个随机试验的结果,可以用一个变量来表示,则这样的变量叫做随机变量. As we all know, probability theory studies random phenomena. To understand random phenomena, one must know all the possible outcomes of random phenomena and the second is to know the probability of each result. For a given random phenomenon, first of all To describe the results that may occur, it is common practice to use numbers to represent possible outcomes and to associate each result with a number. Thus, the concept of random variables emerges: if the results of a random experiment can be used Variables, such variables are called random variables.