我们知道,向量是沟通代数与几何的一座天然的桥梁,向量能进行数量积运算是向量应用广泛的一个重要原因.a与b的数量积a.b的几何意义是:a.b等于a的长度|a|与b在a的方向上的投影|b|cosθ的积,其中θ为a,b的夹角.由于数量积满足分配律,因此,对向量进行数 We know that vector is a natural bridge between algebra and geometry, and the vector can be a product of the number of products is a vector widely used as an important reason.A and b the number of product geometric meaning of ab is: ab is equal to the length of a | a | And b projection in the direction of a | b | cosθ, where θ is the angle between a and b. Since the number product satisfies the distribution law, the number of vectors