题目

设3阶矩阶A=（α1,β,γ）,B=（α2,β,γ）,且|A| =2,|B| =-1,则|A+B| =

提问时间：2020-10-30

答案

|A+B|
= | α1+α2,2β,2γ |
= 4 | α1+α2,β,γ |
= 4 (| α1,β,γ |+ | α2,β,γ |)
= 4(|A|+|B|)
= 4(2-1)
= 4.