JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
Let \(A\) be a symmetric matrix such that \(|A|=2\) and \(\left[\begin{array}{ll}2 & 1 \\ 3 & \frac{3}{2}\end{array}\right] A =\left[\begin{array}{ll}1 & 2 \\ \alpha & \beta\end{array}\right]\). If the sum of the diagonal elements of \(A\) is s, then \(\frac{\beta s}{\alpha^2}\) is equal to \(..........\).
- A \(5\)
- B \(6\)
- C \(7\)
- D \(8\)
Answer & Solution
Correct Answer
(A) \(5\)
Step-by-step Solution
Detailed explanation
\(\left[\begin{array}{ll}2 & 1 \\3 & \frac{3}{2}\end{array}\right]\left[\begin{array}{ll} a & b \\b & c\end{array}\right]=\left[\begin{array}{ll}1 & 2 \\\alpha & \beta\end{array}\right]\) Now \(a c-b^2=2\) and \(2 a+b=1\) and \(2 b + c =2\) solving all these above equations we…
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