Question:

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

WBJEE

Updated On: Apr 25, 2024

(A) 4
(B) 3
(C) -4
(D) -3

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The Correct Option is C

Solution and Explanation

Explanation:

\begin{matrix} A = A^{T} \\ (\begin{array}{cc} 3 & x - 1 \\ 2 x + 3 & x + 2 \end{array}) = (\begin{array}{cc} 3 & 2 x + 3 \\ x - 1 & x + 2 \end{array}) \\ \Rightarrow x - 1 = 2 x + 3 or x = - 4 \end{matrix}

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