A:2种
B:3种
C:4种
D:5种
- Tommy, do you know if Frank ______ to the theatre with us this Sunday if the weather ______.
- Sorry, I have no idea.
(Ⅰ)当α= π3 时,求C1与C2的交点坐标;
(Ⅱ)过坐标原点O做C1的垂线,垂足为A,P为OA中点,当α变化时,求P点的轨迹的参数方程,并指出它是什么曲线.
下列词语中,没有错别字的一组是( )