圆锥曲线的定义既是推导圆锥曲线标准方程的依据,又是用来解决一些问题的重要方法,一般情况下,当问题涉及焦点或准线,且用其它方法不易求解时,可考虑运用定义求解,下面通过一道习题的解答与变形来简单说明 The definition of conic curve is not only the basis of deducing the standard equation of conic curve but also an important method to solve some problems. Generally speaking, when the problem involves the focus or the quasi-line and is difficult to solve by other methods, Below by a solution to the problem and deformation to a brief explanation