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在现行人教版《数学》八年级(上册)第42页,有这样一个“探究问题”:“如图,要在燃气管道l上修建一个泵站,分别向A、B两镇供气.泵站修在管道的什么地方,可使所用的输气管线最短?你可以在l上找几个点试一试,能发现什么规律吗”.这个问题在我们的生活中是很普遍的问题,也是一个很实用的问题.如果我们把这个问题转化为纯数学问题,那就变成了“直线l外有两点A、B,请在直线l上找一点C,使它到A、B两点的距离之和最小.”符合这个条件的点该如何探求寻找呢?
In the current PEP “Mathematics” eighth grade (the first volume) on page 42, there is such a “question of inquiry”: “As shown in the gas pipeline l to build a pumping station, respectively, to the A, B two towns Pumping stations in the pipeline where the repair, gas pipeline can be used to make the shortest? You can find a few points on the point to try to find out what the law? ”The problem in our lives is A very common problem, but also a very practical problem. If we turn this problem into a purely mathematical problem, it becomes “A straight line l two points A, B, please find a little C on the straight line l It is the smallest distance between two points A and B. ”How to find the point that meets this condition?