If $A$ is a $3\times3$ matrix with $|A| = 4$, then $|2A|$ equals:
A32
B8
C64
D16
Answer & Solution
Correct answer: A. 32
For an n×n matrix, |kA| = kⁿ|A|. Here n=3, k=2 ⟹ |2A| = 8·4 = 32.
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