COMEDK · Maths · 21. Matrices
If \(A\) is a matrix of order 3 such that \(|A|=5\), then the value \(|\operatorname{adj} A|\) is
- A 5
- B 25
- C 125
- D 625
Answer & Solution
Correct Answer
(B) 25
Step-by-step Solution
Detailed explanation
\(\begin{array}{ll}|\operatorname{adj} A|=|A|^{n-1} \text {, where } n \text { is order } \\ |\operatorname{adj} A|=(5)^{3-1} \\ |\operatorname{adj} A|=25\end{array}\)
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