概率论提高概率论与数理统计随机推荐probability-statistics-2:概率论:2:第2讲-一维随机变量及其分布:选择题:7:17:1选择题一维随机变量不看本题本题讨论已掌握查看解析收入错题#10874设 XXX 为仅取非负整数值的随机变量,且其 kkk 阶矩存在, k=1,2,⋯k = 1,2,\cdotsk=1,2,⋯,记 Fˉ(i)=P{X≥i},i=0\bar{F}\left(\mathrm{i}\right) = P\{ X \geq i\},i = 0Fˉ(i)=P{X≥i},i=0, 1,2,⋯1,2,\cdots1,2,⋯,则 EX=‾{EX} = \underline{\qquad}EX=.A. ∑i=1∞Fˉ(i)\mathop{\sum }\limits_{i = 1}^{\infty }\bar{F}\left(\mathrm{i}\right)i=1∑∞Fˉ(i)B. ∑i=1∞[Fˉ(i)]2\mathop{\sum }\limits_{i = 1}^{\infty }{\left\lbrack \bar{F}\left(\mathrm{i}\right) \right\rbrack }^{2}i=1∑∞[Fˉ(i)]2C. ∑i=1∞[1−Fˉ(i)]\mathop{\sum }\limits_{i = 1}^{\infty }\left\lbrack {1 - \bar{F}\left(\mathrm{i}\right) }\right\rbracki=1∑∞[1−Fˉ(i)]D. ∑i=1∞[1−Fˉ(i)]2\mathop{\sum }\limits_{i = 1}^{\infty }{\left\lbrack 1 - \bar{F}\left(\mathrm{i}\right) \right\rbrack }^{2}i=1∑∞[1−Fˉ(i)]2