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Question
If A is a square matrix of order 3 and |A| = 5, then |adj A| = ______.
Options
5
25
125
`1/5`
Solution
If A is a square matrix of order 3 and |A| = 5, then |adj A| = 25.
Explanation:
|adj A| = |A|n–1
⇒ |adj A| = 25
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