(A,E)=
1 0 0 1 0 0
4 -1 3 0 1 0
-2 0 2 0 0 1
r2-4r1,r3+2r1
1 0 0 1 0 0
0 -1 3 -4 1 0
0 0 2 2 0 1
r3*(1/2), r2-3r3, r2*(-1)
1 0 0 1 0 0
0 1 0 7 -1 3/2
0 0 1 1 0 1/2
A^-1=
1 0 0
7 -1 3/2
1 0 1/2
(A,E)=
1 0 0 1 0 0
4 -1 3 0 1 0
-2 0 2 0 0 1
r2-4r1,r3+2r1
1 0 0 1 0 0
0 -1 3 -4 1 0
0 0 2 2 0 1
r3*(1/2), r2-3r3, r2*(-1)
1 0 0 1 0 0
0 1 0 7 -1 3/2
0 0 1 1 0 1/2
A^-1=
1 0 0
7 -1 3/2
1 0 1/2