离散型随机变量的分布列整体地反映了随机变量所有可能的取值及其相应值的概率,全面描述了随机变量的统计规律,它是求解离散型随机变量两种最重要的特征数,即期望与方差的“桥梁”,而研究随机变量的特征数则是概率与统计的重要任务之一．故此,从 2000年开始至今的新课程高考数学试卷中,离散性随 The distribution of discrete random variables reflects the probabilities of all possible values ​​of random variables and their corresponding values ​​in a whole. It fully describes the statistical laws of random variables, which are the two most important characteristics for solving discrete random variables, that is, Expectations and variance “bridge”, and the study of the characteristics of random variables is one of the important tasks of probability and statistics. Therefore, from the beginning of 2000 to the present college entrance examination mathematics papers, discreteness with