概车纶与款理统外「 当2≤x<3时，01 2 3 F(x)=P{X≤x} =P(X=0)+P(X=1H+P(X=2)=>P 1,3,37 88881 当x≥3时， F(x)=P(X<x)=P(X=0)+P(X=1) +P{X=2+P{X=3} =∑p=1. x:≤3当 2  x  3时, ; 8 7 8 3 8 3 8 1 = + + = 当 x  3时, F(x) = P{X  x} F(x) = P{X  x}   = xi 2 pi = P{X = 0} + P{X = 1}+ P{X = 2} x • o • 1 • 2 • 3  = 1.  = 3 i x i p = P{X = 0}+ P{X = 1} + P{X = 2}+ P{X = 3}