抛物线在第一象限内图像上一点处的切线与x轴交点的横坐标即为 ,其中,若,则等于( )
Suppose the least distance fron poinrs of the xurve(曲线)to the y-axis is then the velue of a is
设为椭圆上一点,且,,其中为椭圆的两个焦点,则椭圆的离心率e的值等于
当x.yi满足条件时,变量U=的取值范围是
等差数列中有两项和,满足、,则该数列前mk项之和是
Ahyperbola(双曲线)wjthvertices(顶点)(-2,5)and(-2,-3),has an asynptote(渐近线)that passes the point(2.5) Then an equarionk of the hyperbola is