A是三阶矩阵,|A|=2,A的伴随矩阵是A*,则|2A*|=

Question

如题所述

Answer 1

|2A*|= 2^3|A*| = 8 |A|^(3-1) = 8* 2^2 = 32
用到2个性质
1.|kA| = k^n|A|
2.|A*| = |A|^(n-1)