SOLUTION: A and B are two square matrices of rank 2. If |-2AB|=48, |B|=2, what is |A|?

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Question 1099794: A and B are two square matrices of rank 2. If |-2AB|=48, |B|=2, what is |A|?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
abs%28-2AB%29=48
abs%28B%29=2
You also know that,
abs%28AB%29=abs%28A%29%2Aabs%28B%29
and
abs%28kA%29=k%5En%2Aabs%28A%29
So then,
abs%28AB%29=12
and
abs%28A%29=abs%28AB%29%2Fabs%28B%29
abs%28A%29=12%2F2
abs%28A%29=6