平面向量具有几何形式和代数形式的双重身份,是数形结合的重要载体.平面向量的夹角是其中的一个重要知识点,是学习平面向量的数量积的基础,经常出现在各类试题中.本文主要介绍平面向量的夹角的定义、范围、注意事项、易错点、求法,以供参考.1.平面向量的夹角的定义 Plane vector with geometric and algebraic forms of dual identity, is an important carrier of the combination of number.Plane vector angle is one of the important knowledge points, is the number of learning plane vector basis, often appear in various types of questions This paper mainly introduces the definition, scope, precautions, easy to make mistakes and seek for the angle of plane vector for reference.1.The definition of the included angle of plane vector