平面向量的数量积是平面向量的核心内容,同时是高考考查的热点.平面向量的数量积分坐标形式与几何形式,利用这两种形式及相关的性质不仅可以解决平面向量的长度、角度、垂直等问题,还可以解决一些函数的最值问题,往往收到化繁为简、化难为易的效果.下面举例说明平面向量数量积性质的应用.一、求解两向量垂直问题 The quantity product of plane vector is the core content of plane vector and the hot spot of college entrance examination.The number of plane vectors is the integral coordinate form and geometric form.The use of these two forms and related properties can not only solve the length, angle, vertical And so on, but also can solve the most value problems of some functions, and often receive the effect of simplifying and simplifying the problem. The following example illustrates the application of the quantitative product of plane vectors. First, solving two vector vertical problems