向量法与综合法和解析法被认为是研究几何的三种重要方法,向量法在处理有关长度、角度、平行与垂直等问题时,有其独到之处,下面仅仅谈用向量法研究一类平面几何证明与求值问题的一些方法。例1.已知M是■ABCD边AB的中点,DM交对角线AC于N,利用向量法求点N分ANNC所成的比λ的值? Vector method and synthesis method and analytic method are considered as three important methods to study geometry. Vector method has its unique features when it comes to dealing with problems such as length, angle, parallelism and verticality. The following only discusses the use of vector method to study a class Some Methods of Proving and Evaluating Plane Geometry. Example 1. Known M is ■ ABCD edge of the midpoint of AB, DM diagonal AC in N, using the vector method to find the point N points ANNC value?