4、若 sim N(0,1), 则 (|X|gt 2)= ()-|||-(A) [ 1-(1)(2)] ; (B) (1)(2)-1; (C) 2-ϕ(2); (D) https:/img.zuoyebang.cc/zyb_9a198fbc16422e7ebd03be3f9882ac80.jpg-2Phi (2)

[题目]设随机变量 sim N((2,2)^2) ,且 +bsim N(0,1) 则-|||-()-|||-A、 a=2 b=-2-|||-B、 =-2, b=

若_(i)sim N(0,1), =1,2,(X)_(1),(X)_(2)独立，则_(i)sim N(0,1), =1,2,(X)_(1),(X)_(2)()A

xi sim N(0,1) , =2s-1,则xi sim N(0,1) , =2s-1,( )。A.xi sim N(0,1) , =2s-1,B.xi

设1 2 4 0-|||-2 1 3 1-|||-1 0 2 -2-|||-__-|||-2 2 1 1，则1 2 4 0-|||-2 1 3 1-|||-1

已知随机变量sim N(1,(2)^2) sim N(0,1)，并且它们相互独立，则sim N(1,(2)^2) sim N(0,1)_________.已知随

已知矩阵1 2 -1 1-|||-A= 3 8 0 2-|||--1 0 4 __-2-|||-__，1 2 -1 1-|||-A= 3 8 0 2-|||--

=dfrac (1)({X)^2}, 则()-|||-A、 sim (chi )^2(n) B、 sim (chi )^2(n-1) C、 sim F(n,1)

4.-|||-1 2-|||-a1= 2 a2= -1-|||-设向量 -1 1 则向量a 1:a2的内积 [ (a)_(1):(a)_(2)] = ()-||

设行列式1 2 2 3-|||-1 2 -4 -1-|||-0 3 -1 2-|||--2 1 -3 -1 ，则 1 2 2 3-|||-1 2 -4 -1-|

若 Y=X_(1)+X_(2)，X_(i) sim N(0,1)，i=1,2，则（）A. $E(Y)=0$；B. $D(Y)=2$；C. $Y \sim N(0