If $A$ is a $3\times3$ matrix with $|A| = 5$, then $|\,\text{adj}\,A\,|$ equals:
A25
B125
C5
D15
Answer & Solution
Correct answer: A. 25
For an n×n matrix, |adj A| = |A|^{n−1}. Here |adj A| = 5² = 25.
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