在解析几何中,常会遇到这样的问题,即在圆锥曲线上探寻一点,使之到某一定点及到焦点(或可转化为到准线)的距离之和(或差)具有最大值(或最小值).解决这类问题,若是通过设立动点的坐标,建立目标函数来处理,则会因运算量大而最终无功而返.若能紧扣曲线定义,结合曲线的几何性质来解 In analytical geometry, it is often encountered the problem of finding a point on the conic curve so that the sum (or difference) of the distance (or difference) to a given point and to the focal point (or to the collimation line) has a maximum value ( Or minimum). To solve this kind of problem, if we set up the objective function by setting the coordinates of the moving point, we will end up with no return due to the large amount of computation. If the curve definition can be closely linked with the geometric properties of the curve, solution