§1.4向量和矩阵范数 >向量范数( vector norms) 定义1:R空间的向量范数‖·‖,对任意xye满足下列条件 (1)‖x‖≥20;‖x=0x=0 (2)‖x=|‖x对任意eC (3)‖x+y⊥‖x+y列 物常用向量范数: x;=2|x1 max x 1≤isn i=1§1.4 向量和矩阵范数 ➢ 向量范数 ( vector norms ) n x y  R   , 对任意 定义1：Rn空间的向量范数 || · || ,对任意 满足下列条件 (1) || || 0 ; || || 0 0     x  x =  x = (2) || x || | | || x ||    =    C (3) || x y || || x || || y ||     +  + 常用向量范数：  = = n i i x x 1 1 || || | |   = = n i i x x 1 2 2 || || | |  || || max | | 1 i i n x x    = 