概率伦与款程统外 0 当0≤x<1时， F-PK≤=PX=- 当x≥1时， F(x)=P{X≤x} 0,x<0, =P{X=0HP{X=1}得F(x)= 0≤x<1, 11 221. 1,x≥1. • 0 • 1 x 当 0  x  1时, F(x) = P{X  x}= P{X = 0} ; 2 1 = 当 x  1时, F(x) = P{X  x} = P{X = 0}+ P{X = 1} 2 1 2 1 = + = 1.            = 1, 1. , 0 1, 2 1 0, 0, ( ) x x x 得 F x