平面向量数量积的运算是高考的热点之一,大多在选择题和填空题中以平面图形及平面几何知识为载体出现,属于基础题、中档题中的常规题型,对平面向量数量积的考查一般有两种题型,一是给出条件求数量积,二是给出数量积,求模长、夹角或参数的值,备考过程中要切实分清此类问题的题型,用恰当的方法迅速正确求解。一、用坐标法解决求向量数量积的问题 The calculation of the number of plane vectors is one of the hot spots in college entrance examination, mostly in the multiple choice questions and fill in the blank questions to plane graphics and plane geometry knowledge as the carrier, belonging to the basic questions, mid-range questions in the conventional questions, the number of planar vector product There are two general test questions, one is to give the conditions for the number of products, the second is to give the number of product, the length of the model, the angle or parameter values, the preparation process should be effective in the classification of such questions, with appropriate The method is solved quickly and correctly. First, use the coordinate method to solve the problem of vector quantity product