JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
Let \(A\) be a \(3 \times 3\) matrix such that \(A^T \begin{bmatrix}1\\0\\1\end{bmatrix} = \begin{bmatrix}5\\2\\2\end{bmatrix}\), \(A^T \begin{bmatrix}0\\0\\1\end{bmatrix} = \begin{bmatrix}3\\1\\1\end{bmatrix}\), \(A \begin{bmatrix}1\\0\\1\end{bmatrix} = \begin{bmatrix}3\\4\\4\end{bmatrix}\) and \(A \begin{bmatrix}0\\0\\1\end{bmatrix} = \begin{bmatrix}1\\3\\1\end{bmatrix}\). If \(\det(A) = 1\), then \(\det(\operatorname{adj}(A^2 + A))\) is equal to:
- A \(16\)
- B \(25\)
- C \(49\)
- D \(64\)
Answer & Solution
Correct Answer
(D) \(64\)
Step-by-step Solution
Detailed explanation
Let \(C_1, C_2, C_3\) be the columns of \(A\) and \(R_1, R_2, R_3\) be the rows of \(A\). From the given equations, we have: \(A \begin{bmatrix}0\\0\\1\end{bmatrix} = C_3 = \begin{bmatrix}1\\3\\1\end{bmatrix}\)…
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