例1.如下图,牧童在A处放牛,其家在B处,A、B到河岸的距离分别为AC、BD,已知AC=200米,BD=600米,且CD=600米.(1)牧童从A处放牛牵到河边饮水后再回家,试问在何点处饮水,所走路程最短?(2)最短路程是多少?【考点】轴对称—最短路线问题.【分析】(1)要求牧童行驶距离最短的饮水点P,除非AP、BP的和为两定点之间的距离,也即是P在两定点F、B的连线上. Example 1. The following picture shows the shepherd’s cow being cowed at A, his home being at B, and the distance from A, B to the bank is respectively AC, BD, known as AC = 200 m, BD = 600 m, and CD = 600 m. (1) Shepherd boy put cattle from A to go back to the river to drink water, where is the point of drinking water, the shortest distance? (2) What is the shortest distance [test center] Axisymmetry - the shortest route problem. Analysis】 (1) Require the shepherd to drive the shortest drinking water point P, unless the sum of AP and BP is the distance between two fixed points, that is, the connection of P at the two fixed points F and B.