西安毛子科技大学XIDIAN UNIVERSITYanx, +a2x2+...+anx,=ba21Xj + a22X2 + ... +a2nx=b,(1)设线性方程组asixi +asx2 +... +asnx,=b,其系数矩阵A和增广矩阵A分别为anla2aila1216a21a22a21a22a2nVA=b.as1as2a.as1asuVsn设线性方程组 (1) 11 1 12 2 1 1 21 1 22 2 2 2 1 1 2 2 n n n n s s sn n s a x a x a x b a x a x a x b a x a x a x b  + + + =  + + + =   + + + =  11 12 1 21 22 2 1 2 , n n s s sn a a a a a a A a a a     =       11 12 1 1 21 22 2 2 1 2 n n s s sn s a a a b a a a b A a a a b     =       其系数矩阵A和增广矩阵 A 分别为