题目
设X_1, X_2是随机变量，其分布函数分别为F_1(x), F_2(x)，为使F(x) = aF_1(x) + bF_2(x)是某一随机变量的分布函数，在下列给定的各组数值中应取( )A. a = (3)/(5), b = (2)/(5)B. a = (2)/(3), b = (2)/(3)C. a = -(1)/(2), b = (3)/(2)D. a = (1)/(2), b = (3)/(2)
设$X_1, X_2$是随机变量，其分布函数分别为$F_1(x), F_2(x)$，为使$F(x) = aF_1(x) + bF_2(x)$是某一随机变量的分布函数，在下列给定的各组数值中应取( )
A. $a = \frac{3}{5}, b = \frac{2}{5}$
B. $a = \frac{2}{3}, b = \frac{2}{3}$
C. $a = -\frac{1}{2}, b = \frac{3}{2}$
D. $a = \frac{1}{2}, b = \frac{3}{2}$
题目解答
答案
A. $a = \frac{3}{5}, b = \frac{2}{5}$