题目

Long years of hard work made______possible for him to enter a key university in Bingjing. A. that                        B. this                  C. which                          D. it 答案:D已知椭圆的离心率e= ,左、右焦点分别为F1、F2 , 定点,P(2, ),点F2在线段PF1的中垂线上.(Ⅰ)求椭圆C的方程;(Ⅱ)设直线l:y=kx+m与椭圆C交于M、N两点,直线F2M、F2N的倾斜角分别为α、β且α+β=π,求证:直线l过定点,并求该定点的坐标.
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