向量作为一种解题工具,应用极为广泛,一直是高考和高中数学联赛的重点考查内容.向量知识融数形于一体,为我们解决数学问题提供了更为广阔的思维空间.本文通过构造向量、活用向量的数量积把一些非向量的代数题转化为向量问题,从而使运算简捷,易学易懂.一、求代数式的最值例1(2015年浙江高考题)若实数x,y Vector as a solution to a wide range of applications, has been the focus of the college entrance examination and high school mathematics exam content.Vector knowledge fusion in one form, for our solution to mathematical problems provide a broader space of thought.This paper constructs a vector , The number of active vectors to some non-vector algebra problems into vector problems, so that the operation is simple, easy to learn. First, find the maximum of algebraic example 1 (2015 Zhejiang college entrance examination) If the real number x, y