1 3 4 0, x<0 0.6, 0≤x<1 F(x)= 0.6+0.6×0.4, 1≤x<2 0.6+0.6×0.4+0.6×0.42， 2≤x<3 0.6(1+0.4+0.42+0.43) 3≤x<4 1 x≥4• 0 • 1 • 2 • 3 • 4 x x ] ] 0.6 0.6 0.4, + × 1 2 ≤ < x 0.6, 0 1 ≤ < x 0, x < 0 2 0.6 0.6 0.4 0.6 0.4 , +×+× 2 3 ≤ < x 2 3 0.6(1 0.4 0.4 0.4 ) ++ + 3 4 ≤ < x 1 x ≥ 4 F x( ) = ]• • • ]