题目　设抛物线C :y2 =8x ,若椭圆D的左焦点F和相应的左准线l分别与抛物线图 1　题目 1图的焦点、准线重合 ,椭圆短轴的一个端点为B ,且线段BF的中点M到定点A(m ,0 )的距离的最小值是 3,试求实数m的值及此时的椭圆方程 .错解　设所求椭圆的中心为O′(n ,0 ) ,所求的椭圆方程是( The subject sets the parabola C:y2 =8x, if the left focus F of the ellipse D and the corresponding left guideline l overlap with the focus and the quasi-line of the graph 1 of the parabola 1 respectively, an endpoint of the short axis of the ellipse is B, and the line segment BF The minimum value of the distance from the middle point M to the fixed point A(m, 0) is 3. Try to find the value of the real number m and the elliptic equation at this time. The wrong solution sets the center of the desired ellipse to O’(n, 0). The elliptic equation sought is (