【单选题】根据以下内容回答题: Adam Smith,writing in the 1770s,was the first person to see the importance of the divi-sion of labor and to explain part of its advantages.He gives as an example the process by which pins w...
【单选题】根据以下内容回答题: Adam Smith,writing in the 1770s,was the first person to see the importance of the divi-sion of labor and to explain part of its advantages.He gives as an example the process by which pins w...
【简答题】已知椭圆: x 2 a 2 + y 2 b 2 =l(a>b>0)的一个顶点坐标为B(0,1),若该椭圆的离心率等于 3 2 . (1)求椭圆的方程. (2)Q是椭圆上位于x轴下方的一点,F 1 F 2 分别是椭圆的左、右焦点,直线QF 1 的倾斜角为 π 6 ,求△QF 1 F 2 的面积; (3)以B为直角顶点作椭圆的内接等腰直角三角形ABC,判断这样的三角形存在吗?若存在,有几个?若不存在,...