2…1 11∴2.2 所以,线性方 D 0 程组的解唯一 (i≠m)1n-12…1 n1…2…1 0 D L≠n D =2D D =2 D1 1 1 1 1 1 2 1 1 1 1 1 1 1 1 D n n = ( ) i n  − = 0 i i D x D = 所以，线性方 程组的解唯一 = 2D n n D x D = ( ) i n  = 2 = 0 2 2 2 2 1 1 1 1 1 1 1 1 1 1 2 1 1 1 1 1 1 1 1 D n n = − 2 2 2 2 D n Di