WBJEE · Maths · Matrices
If \(A=\left(\begin{array}{cc}3 & x-1 \\ 2 x+3 & x+2\end{array}\right)\) is a symmetric matrix, then the value of \(x\) is
- A 4
- B 3
- C -4
- D -3
Answer & Solution
Correct Answer
(C) -4
Step-by-step Solution
Detailed explanation
Hints: \(A=A^T\) \(\begin{aligned} & \left(\begin{array}{cc} 3 & x-1 \\ 2 x+3 & x+2 \end{array}\right)=\left(\begin{array}{cc} 3 & 2 x+3 \\ x-1 & x+2 \end{array}\right) \\ & \Rightarrow x-1=2 x+3 \text { or } x=-4 \end{aligned}\)
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