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Question
If A is a square matrix of order 3, |A′| = −3, then |AA′| = ______.
Options
9
−9
3
−3
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Solution
If A is a square matrix of order 3, |A′| = −3, then |AA′| = 9.
Explanation:
|AA'| = |A||A'|
= (−3)(−3)
= 9
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