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题目(2013年全国高考大纲卷数学理科试题)椭圆C:x24+y23=1的左、右顶点分别为A1、A2,点P在C上且直线PA2的斜率的取值范围是[-2,-1],那么直线PA1的斜率的取值范围是().A.[1/2,3/4] B.[3/8,3/4]C.[1/2,1] D.[3/4,1]解析:设P点坐标为(x,y),可得直线PA2的斜率k2=y/x-2,直线PA1的斜率k1=y/x+2.因为P点在椭圆上,可得
Title (2013 national college entrance examination outline volume mathematics science test questions) ellipse C: x24 + y23 = 1 left and right vertices are A1, A2, point P in C and the straight line PA2’s slope is in the range of [-2, -1], then the range of the slope of the straight line PA1 is (). A.[1/2,3/4] B.[3/8,3/4]C.[1/2,1] D. [3/4, 1] Analysis: Let P coordinate be (x, y), the slope of the straight line PA2 is k2 = y/x-2, and the slope of the straight line PA1 is k1 = y/x+2. Because the P point is Oval, available