应用空间向量证明立体几何中的“共点”、“共线”、“共面”等问题,比较以前传统的纯几何证明,要简单快捷,也大大减少了思维难度,使解题变得程序化.这也是几何问题 The application of space vector to prove the “common point”, “collinearity”, “coplanarity” and other issues in the three-dimensional geometry, compared with the previous traditional pure geometric proof, it is simple and quick, and it also greatly reduces the difficulty of thinking. Make the problem procedural. This is also a geometric problem