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椭圆诊断检测一、选择题 1.F1,F2是定点,|F1F2|=8,动点M满足|MF1|+|MF2|=8,则M点的轨迹是( ) (A)椭圆. (B)直线. (C)圆. (D)线段. 2. 椭圆x2/25+y2/9=1上的点P到左准线的距离为2.5,那么P到右焦点的距离为( ) (A)8. (B)25/6. (c)9/2. (D)15/8. 3.椭圆短轴长是2,长轴长是矩轴长的2倍,则椭圆中心到准线的距离是( )
Ellipse diagnosis test 1. Multiple choice questions 1.F1, F2 are fixed points, |F1F2|=8, and the moving point M satisfies |MF1|+|MF2|=8, then the trace of M point is () (A) ellipse. (B ) Straight line. (C) Circle. (D) Line segment. 2. The distance P from the point P on the ellipse x2/25+y2/9=1 to the left guideline is 2.5, then the distance P from the right focus is () (A ) 8. (B)25/6. (c)9/2. (D)15/8. 3. The length of the short axis of the ellipse is 2. The length of the long axis is twice the length of the axis of the axis. Then the center of the ellipse is aligned with the guideline. The distance is ()