(mu ,dfrac ({sigma )^2}(n))-|||-C.N(0,1)-|||-D.N(0,σ^2)

设 X sim N(mu, sigma^2)，要使 Y sim N(0,1)，则A. $Y = \sigma X + \mu$B. $Y = \sigma X

(overline (X))=dfrac ({sigma )^2}(n)-|||-C. (overline (X)-mu )=dfrac ({sigma )^2

(sim N(mu ,(sigma )^2),sim N(mu ,(sigma )^2),sim N(mu ,(sigma )^2),sim N(mu ,(si

N(-1,2)-|||-D N(0,1)

-1 0 -1 0 0 的值为 ()-|||-A 1-|||-B ((-1))^dfrac (n(n-1){2)}-|||-C -1-|||-D ((-1))

已知随机变量X ~N(0,1),则Y=-2 X+3服从的分布为()A.N(3,6)B.N(3,7)C.N(3,5)D.N(3,4)已知随机变量X~N(0,1),

A.approx N(0,1)B.approx N(0,1)C.approx N(0,1)D.approx N(0,1)设连续性随机变量X和Y相互独立，且，Y的

的值为 .-|||-n-1 0 ...0 0 0-|||-0 0 ...0 0 n-|||-A ((-1))^dfrac ((n-1)(n-2){2)n!}!-

设随机变量的概率密度为，则A.N ( -2 , 2 )B.N ( -2 , 4 ) C.N ( -2 , 8 ) D.N ( -2 , 16 )设随机变量的概率

(D) dfrac ((n-1){S)^2}({sigma )^2}sim (chi )^2(n)