WBJEE · Maths · Matrices
Let \(A\) be a \(3 \times 3\) matrix and \(B\) be its adjoint matrix. If \(|B|=64,\) then \(|A|\) is equal to
- A ±2
- B \(\pm 4\)
- C \(\pm 8\)
- D ±12
Answer & Solution
Correct Answer
(C) \(\pm 8\)
Step-by-step Solution
Detailed explanation
We have, \(|B|=64\) \(\Rightarrow |\operatorname{adj} A \mid=64\) \(\Rightarrow|A|^{2}=64\) \(|A|=\pm 8\)
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