JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
The positive value of the determinant of the matrix \(A\), whose \(A d j(A d j(A))=\left(\begin{array}{ccc}14 & 28 & -14 \\ -14 & 14 & 28 \\ 28 & -14 & 14\end{array}\right)\), is
- A \(13\)
- B \(14\)
- C \(15\)
- D \(16\)
Answer & Solution
Correct Answer
(B) \(14\)
Step-by-step Solution
Detailed explanation
\(\operatorname{Adj}(\operatorname{Adj} A)=\left[\begin{array}{ccc}14 & 18 & -14 \\ -14 & 14 & 28 \\ 28 & -14 & 14\end{array}\right]\)…
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