A 1 B 0.4 C 0.8 D 0.7设X的分布律为:F(x)为其分布函数,则F(2)=_.A1B0.4C0.8D0.7
(-1,1) D. [ -1,1]
-1 或1; D. -1 或2.
-dfrac (1)(pi )-|||-D. dfrac (1)(pi )
-i; C.1;D. -1.
(-2,1] D. (-2,1)
[ -1,1] C. [ -1,0] D.
1/2 C.0 D. -1-|||-__
1/4 C. 4/1 D. /11
sqrt (dfrac {a)(a-1)} D. 3