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Question
Let A be a nonsingular square matrix of order 3 × 3. Then |adj A| is equal to ______.
Options
|A|
|A|2
|A|3
3|A|
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Solution
Let A be a nonsingular square matrix of order 3 × 3. Then |adj A| is equal to |A|2.
Explanation:
Offended, we know that |adj A| = |A|n−1 where n = 3
∴ |adj A| = |A|2
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