Question

帮我写一下线性代数题设A为三阶矩阵,若已知|A|=m,求|-mA|

Answer 1

知识点:

设A为n阶方阵, 则 |kA| = k^n|A|.

所以有 |-mA| = (-m)^3 |A| = -m^3 * m = -m^4