【简答题】The line from Alexander Pope was to emphasize the importance of ________.
【单选题】已知点P(2,-3)、Q(3,2),直线ax-y+2=0与线段PQ相交,则a的取值范围是( )
【简答题】Your ad should emphasize the most important ___________.
【单选题】如图,已知F 1 ,F 2 是椭圆 C: x 2 a 2 + y 2 b 2 =1 (a>b>0)的左、右焦点,点P在椭圆C上,线段PF 2 与圆x 2 +y 2 =b 2 相切于点Q,且点Q为线段PF 2 的中点,则椭圆C的离心率为( )
【单选题】已知A(1,0)、B(5,3),则线段AB的长度为
【单选题】已知点A(2,3),B(8,-3),则线段AB中点的坐标为( )