已知点F是双曲线x2a2-y2b2=1(a>0,b>0)的右焦点,点C是该双曲线 发布时间:2017-04-29 17:05 │ 来源:www.tikuol.com 题型:选择题 问题: 已知点F是双曲线x2a2-y2b2=1(a>0,b>0)的右焦点,点C是该双曲线的左顶点,过F且垂直于x轴的直线与双曲线交于A、B两点,若△ABC是锐角三角形,则此双曲线离心率的取值范围是( )A.(1,2)B.(1,+∞)C.(2,1+2)D.(1,1+2)
题型:选择题 When the old man_____to walk back to his house,the sun____itself behind the mountain.A.was starting;hidB.had started;had already hiddenC.had started;was hidingD.started;had already hidden 查看答案