43.
Circle C and line k lie in the xy-plane. If circle C is centered at the
origin and has radius 1, does line k intersect circle C ?
(1) The x-intercept of line k is greater than 1.
(2) The slope of line k is - .
【答案】E
【思路】
(1) 需要知道兩點才行-----------------------------------------------------
-----------insufficient
(2) slope為負,左上右下無法判斷-------------------------------------------
-----------insufficient
(1)(2)-------------------------------------------------------------------
-----------insufficient
我觉得应该是选c, 因为有截距(大于1)和斜率(负1/10), 可以知道相交情况的啊
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