(A,E) =
2 2 3 1 0 0
1 -1 0 0 1 0
-1 2 1 0 0 1
r1+2r3,r2+r3得
0 6 5 1 0 2
0 1 1 0 1 1
-1 2 1 0 0 1
r1-6r2,r3-r2得
0 0 -1 1 -6 -4
0 1 1 0 1 1
-1 0 -1 0 -2 -1
r2+r1,r3-r1得
0 0 -1 1 -6 -4
0 1 0 1 -5 -3
-1 0 0 -1 4 3
r1r3
-1 0 0 -1 4 3
0 1 0 1 -5 -3
0 0 -1 1 -6 -4
r1*-1,r3*-1
1 0 0 1 -4 -3
0 1 0 1 -5 -3
0 0 1 -1 6 4
故：A的逆矩阵为：
1 -4 -3
1 -5 -3
-1 6 4