If A = [ * 20 c 4& x + 2 2x - 3 & x + 1 ]is symmetric, then x = - Vidyadip

MCQ

If $A = \left[ {\begin{array}{*{20}{c}}4&{x + 2}\\{2x - 3}&{x + 1}\end{array}} \right]$is symmetric, then $ x =$

A
$3$
✓
$5$
C
$2$
D
$4$

✓

Answer

Correct option: B.

$5$

b
(b) Since the given matrix is symmetric, therefore

${a_{12}} = {a_{21}} \Rightarrow x + 2 = 2x - 3 \Rightarrow x = 5$.

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