(1)直線
的方程可化為
,
直線
的斜率
,······················································································ 2分
因為
,
所以
,當且僅當
時等號成立.
所以,斜率
的取值范圍是
.·································································· 5分
(2)不能.··········································································································· 6分
由(Ⅰ)知
的方程為
,其中
.
圓
的圓心為
,半徑
.
圓心
到直線
的距離
.························································································· 9分
由
,得
,即
.從而,若
與圓
相交,則圓
截直線
所得的弦所對的圓心角小于
.
所以
不能將圓
分割成弧長的比值為
的兩段。ぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁぁ 12分