JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
For \(\alpha, \beta \in \mathrm{R}\) and a natural number \(\mathrm{n}\), let \(A_r=\left|\begin{array}{ccc}r & 1 & \frac{n^2}{2}+\alpha \\ 2 r & 2 & n^2-\beta \\ 3 r-2 & 3 & \frac{n(3 n-1)}{2}\end{array}\right|\). Then \(2 A_{10}-A_8\)
- A \(4 \alpha+2 \beta\)
- B \(2 \alpha+4 \beta\)
- C \(2 n\)
- D \(0\)
Answer & Solution
Correct Answer
(A) \(4 \alpha+2 \beta\)
Step-by-step Solution
Detailed explanation
\(A_r=\left|\begin{array}{ccc}r & 1 & \frac{n^2}{2}+\alpha \\ 2 r & 2 & n^2-\beta \\ 3 r-2 & 3 & \frac{n(3 n-1)}{2}\end{array}\right|\)…
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