A的特征值为 2,2,-4
所以 |A| = 2*2*(-4) = -16.
| (-1/2A*)^-1 |
= | (-1/2 |A|A^-1)^-1 |
= | (8A^-1)^-1|
= | (1/8) A|
= (1/8)^3 |A|
= -1/32.(-1/2)^-1不是-2吗？提出来以后应该是-8才对吧而且A*=A |A| ，那么（A*）^-1应该是(A |A| )^-1吧答案是-1/2哦(A*)^-1 = (|A|A^-1)^-1 = (1/|A|) A1/|A| 提出行列式后是 1/|A|^3乘 |A| 后为 1/|A|^2再乘 -8= -8 / 16^2= -1/32