题目

已知,如图,,点在第二象限运动,求的最小值为( ).A. B. C. D. 答案:【答案】D【解析】根据题意知点P的运动轨迹是以点M为圆心,半径的圆弧,当点P在BC上时,PC有最小值,据此可求解.如图,∵A(-1,0),B(-3,0),∴AB=2,∵∠APB=30°,∴点P的轨迹是以M为圆心,半径r=2的圆弧;易得圆心坐标为, ,.故选If you ______ earlier, you ________ him.A.came; would meetB.had come; would have metC.had come; would meetD.would come; met
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