解决立体几何问题常有二条途径:一是几何法,二是向量法。几何法主要以逻辑推理论证的程序步骤去解决问题,对培养同学们的抽象思维能力和空间想象能力大有裨益。向量法因选取“工具”不同,可分为基向量法和坐标向量法。基向量法是以“基底”为工具进行推理演算,关键是将所解决问题中涉及的所有向量用一组基底来表示,这一组基底最好已知(或可求)它们的模和两两向量的夹角。常用向量的数量积来 There are two ways to solve the problem of three-dimensional geometry: one is the geometric method, the other is the vector method. Geometry mainly uses procedural steps of logical reasoning and argumentation to solve the problem, and is of great help in cultivating students’ abilities of abstract thinking and spatial imagination. Due to different selection of “vector”, vector method can be divided into basic vector method and coordinate vector method. The basic vector method is based on “base ” as a tool. The key point is that all the vectors involved in the problem to be solved are represented by a group of bases, which are best known (or available) And two vector angle. The number of commonly used vector to