(1).p=C(10,2)*(0.6)^2*(0.4)^8=0.0106.
(2)P(ξ≥1)=1-P(ξ=0)=1-e^(-2)=0.8647;Eξ=2;
Eξˆ2=Dξ+(Eξ)^2=2+2^2=6.
(3)[n=ξ-2/√3应为n=(ξ-2)/√3吧!]n=(ξ-2)/√3~N(0,1).
若F(x)是ξ的分布函数,则F(2)=0.5.
P(n ≥0)= 0.5.D(-ξ+1 )=Dξ=3.
(4)p{ξ=2}=0.
p{|ξ-8|
(1).p=C(10,2)*(0.6)^2*(0.4)^8=0.0106.
(2)P(ξ≥1)=1-P(ξ=0)=1-e^(-2)=0.8647;Eξ=2;
Eξˆ2=Dξ+(Eξ)^2=2+2^2=6.
(3)[n=ξ-2/√3应为n=(ξ-2)/√3吧!]n=(ξ-2)/√3~N(0,1).
若F(x)是ξ的分布函数,则F(2)=0.5.
P(n ≥0)= 0.5.D(-ξ+1 )=Dξ=3.
(4)p{ξ=2}=0.
p{|ξ-8|