Question

If $A=\left(\begin{array}{cc}3& x-1\\ 2x+3& x+2\end{array}\right)$ is a symmetric matrix, then the value of $x$ is

• (A) 4
• (B) 3
• (C) -4
• (D) -3

Answer 1

The Correct Option is C

Explanation:
$$\begin{array}{c}A=A^T\\ \left(\begin{array}{cc}3& x-1\\ 2x+3& x+2\end{array}\right)=\left(\begin{array}{cc}3& 2x+3\\ x-1& x+2\end{array}\right)\\ \Rightarrow x-1=2x+3\text{ or }x=-4\end{array}$$