解析几何中，我们经常遇到求某曲线上一点到两定点的距离之和最小的问题．由于曲线类型的变换，学生很难把握解题的要点．下面就曲线的光学性质在解题中的运用作几点介绍．结论１放置在Ａ点的光源发出的光线，经直线ｌ反射后通过点Ｂ，则反射点Ｐ是直线上所有点中到Ａ，Ｂ... In analytical geometry, we often encounter the problem of finding the smallest sum of the distance from one point to two fixed points on a curve. Due to the transformation of the curve type, it is difficult for students to grasp the main points of the solution. The following is a brief introduction of the use of the optical properties of the curve in the problem solving. Conclusion 1 The light emitted by the light source placed at point A passes through point B after being reflected by the straight line l, and the reflection point P is all points in the straight line to A, B...