——__________?
——It was nice and interesting.
A:Where did you go on vacation
B:When did you go on vacation
C:How was your vacation
D:Did you enjoy your vacation
利用计算机在区间(0,1)上产生两个随机数a和b,则方程x=-2a-b2x有实根的概率为( )
计算x3•x2 的结果是( )
没有错别字的一项是( )