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If A is 3×3 with |A| = -2, then |adj(A)| =
A-4
B-2
C4 (= |A|^(n-1) = (-2)²)
D1
Answer & Solution
Correct answer: C. 4 (= |A|^(n-1) = (-2)²)
|adj(A)| = |A|^(n-1) for n×n matrix. For 3×3: |adj(A)| = |A|² = (-2)² = 4.
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