JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
Let \(A\) be a symmetric matrix of order \(2\) with integer entries. If the sum of the diagonal elements of \(A ^{2}\) is \(1,\) then the possible number of such matrices is
- A \(4\)
- B \(1\)
- C \(6\)
- D \(12\)
Answer & Solution
Correct Answer
(A) \(4\)
Step-by-step Solution
Detailed explanation
\(A=\left(\begin{array}{ll}a & b \\ b & c\end{array}\right), \quad a, b, c \in I\)…
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