在空间立体几何中,角的问题,包括线线角、线面角、面面角等,对很多同学来说是一个难点,关键在于需将这些角转化为平面角.但引进空间向量以后,就不需要转化了,只要通过空间向量的坐标运算,就可以求出角的大小,因此大大地简化了思维过程,是立体几何中求角的一种较好的方法. In spatial three-dimensional geometry, the problem of angles, including line angles, line face angles, face angles, etc., is a difficult point for many students. The key is to convert these angles into planar angles. After the introduction of space vectors, however, It does not need to be converted, as long as the coordinates of the space vector, you can find the size of the angle, which greatly simplifies the thinking process, is a better way to calculate the angle in the three-dimensional geometry.