JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
Let \(A = \begin{bmatrix} 1 & 0 & 0 \\ 3 & 1 & 0 \\ 9 & 3 & 1 \end{bmatrix}\) and \(B = [b_{ij}]\), \(1 \leq i, j \leq 3\). If \(B = A^{99} - I\), then the value of \(\dfrac{b_{31} - b_{21}}{b_{32}}\) is :
- A \(99\)
- B \(199\)
- C \(149\)
- D \(159\)
Answer & Solution
Correct Answer
(C) \(149\)
Step-by-step Solution
Detailed explanation
Let \(A = I + C\), where \(I\) is the identity matrix and \(C = \begin{bmatrix} 0 & 0 & 0 \\ 3 & 0 & 0 \\ 9 & 3 & 0 \end{bmatrix}\). Calculating the powers of \(C\), we get:…
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