[1.3]设(X,Y)的分布律为-|||-Y 1 2 3-|||-X-|||--1 dfrac (1)(3) dfrac (a)(6) dfrac (1)(4)
设随机变量X,Y满足P(XY=0) =1,并且分布律分别为X -1 0 2 Y 0 1-|||-P dfrac (1)(6) dfrac (1)(3) dfra
已知 ( X , Y ) 服从二维正态分布(1,0,4,1,dfrac (1)(2)) ,则 D ( 3 X - 2 Y - 1 ) =_______已知(X,
16.设X与Y相互独立,其分布列分别为-|||-X -2 -1 0 dfrac (1)(2)-|||-p dfrac (1)(4) dfrac (1)(3) d
设X和Y相互独立,且均服从[0,1]上的均匀分布,则P(min{X,Y)≤dfrac (1)(2)}=____设X和Y相互独立,且均服从[0,1]上的均匀分布,
(B) dfrac (1)(2)(X)^2+dfrac (1)(2)(Y)^2 服从x^2分布.-|||-(C) dfrac (1)(3)((X+Y))^2 服
设随机变量X与Y的联合分布律为X/Y 1 2 3-|||-1 1/9 2/9 2/9-|||-2 0 dfrac (1)(9) dfrac (2)(9)-|||
已知(X,Y)服从二维正态分布 (1,0,1,1,dfrac (1)(2)) ,则 (2X-Y-1)=A.3B.2C.OD
[例2]设随机变量X与Y相互独立,其概率分布为-|||-x 0 1-|||-P .dfrac (1)(3) .dfrac (2)(3)-|||-Y 0 1-||
3、设 (x,y)=arctan dfrac (x)(y), 则 (1,1)=-|||-(A)1; (B)0; (C) dfrac {1)(2),dfrac