1000 x,=0 0100 即得 00 0 1-24-7)(0001 =0 故方程组的解为 (4)对系数矩阵实施行变换 313 10 1920 01 411-1316 1717 0000 3 13 17 20 即得 17 17 故方程组的解为 19 k1 7.求解下列非齐次线性方程组: 2x+3y+x=4, 4x1+2x2-x3=2, x-2y+4x=-5, (1){3x1-1x2+2 0, (2) 3x+8y-2x=13, 1lx1+3x2=8; 4x-y+9z=-6;6               − − − − − 1 2 4 7 4 1 3 6 3 1 2 7 2 3 1 5               0 0 0 1 0 0 1 0 0 1 0 0 1 0 0 0 ~ 即得        = = = = 0 0 0 0 4 3 2 1 x x x x 故方程组的解为        = = = = 0 0 0 0 4 3 2 1 x x x x (4) 对系数矩阵实施行变换:               − − − − − 7 2 1 3 4 11 13 16 2 3 3 2 3 4 5 7                 − − 0 0 0 0 0 0 0 0 17 20 17 19 0 1 17 13 17 3 1 0 ~ 即得          = = = − = − 4 4 3 3 2 3 4 1 3 4 17 20 17 19 17 13 17 3 x x x x x x x x x x 故方程组的解为                 − − +                 =               1 0 17 20 17 13 0 1 17 19 17 3 1 2 4 3 2 1 k k x x x x 7．求解下列非齐次线性方程组: (1)      + = − + = + − = 11 3 8; 3 1 2 10, 4 2 2, 1 2 1 2 3 1 2 3 x x x x x x x x (2)        − + = − + − = − + = − + + = 4 9 6; 3 8 2 13, 2 4 5, 2 3 4, x y z x y z x y z x y z