When he ___ the bus , the poor man realized he had left his bag on it.
A:got on
B:got off
C:got to
D:got up
等式y=ax3+bx+c中,当x=0时,y=3;当x=﹣1时,y=5;求当x=1时,y的值.
写出下列字母对应的大小写。
____ ____ ____
已知双曲线x2a2-y22=1(a>2)的两条渐近线的夹角为π3,则双曲线的离心率为( )