01 2,A2=(-1 2+2 3-5 2+3 23 32 2 0 32 3+3 于是可知A的伴随矩阵为 A A 52-1 A2A2A2|=10-22 A34243)(7-211. 2 1 1 0 ( 1) 2, 2 0 1 1 1, ( 1) 1 0 0 1 ( 1) 2, 3 2 1 0 ( 1) 2, 3 5 1 1 2, ( 1) 2 5 0 1 ( 1) 3 3 3 3 3 2 3 2 3 1 3 1 2 3 2 3 2 2 2 2 2 1 2 1 = − = = − = − = − = = − − = − = − − − = = − − = − + + + + + + A A A A A A 于是可知A的伴随矩阵为           − − − − =           = 7 2 1 10 2 2 5 2 1 1 3 2 3 3 3 1 2 2 2 3 2 1 1 2 1 3 1 A A A A A A A A A A ~