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

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

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

JEE STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

Consider the sets $\mathrm{A}=\left\{(\mathrm{x}, \mathrm{y}) \in \mathbb{R} \times \mathbb{R}: \mathrm{x}^{2}+\mathrm{y}^{2}=25\right\}$, $B=\left\{(x, y) \in \mathbb{R} \times \mathbb{R}: x^{2}+9 y^{2}=144\right\}, C=\{(x, y)$ $\left.\in \mathbb{Z} \times \mathbb{Z}: x^{2}+y^{2} \leq 4\right\}$, and $D=A \cap B$. The total number of one-one functions from the set D to the set C is :

The value of $b>3$ for which

$12 \int \limits_{3}^{b} \frac{1}{\left(x^{2}-1\right)\left(x^{2}-4\right)} d x=\log _{e}\left(\frac{49}{40}\right)$, is equal to

The order of the differential equation whose solution is ${x^2} + {y^2} + 2gx + 2fy + c = 0$, is

A stone is falling freely and describes a distance s in $t$ seconds given by equation $s = {1 \over 2}g\,{t^2}$. The acceleration of the stone is

Let the line $\mathrm{L}: \sqrt{2} \mathrm{x}+\mathrm{y}=\alpha$ pass through the point of the intersection $\mathrm{P}$ (in the first quadrant) of the circle $x^2+y^2=3$ and the parabola $x^2=2 y$. Let the line $L$ touch two circles $C_1$ and $C_2$ of equal radius $2 \sqrt{3}$. If the centres $Q_1$ and $Q_2$ of the circles $C_1$ and $C_2$ lie on the $y$-axis, then the square of the area of the triangle $\mathrm{PQ}_1 \mathrm{Q}_2$ is equal to........................

Consider the equation ${x^2} + \alpha x + \beta = 0$ having roots $\alpha ,\beta $ such that $\alpha \ne \beta $ .Also consider the inequality $\left| {\left| {y - \beta } \right| - \alpha } \right| < \alpha $ ,then

$A=\left[\begin{array}{l}a_{i j}\end{array}\right]_{m\times n}$ is a square matrix, if

The incentre of the triangle with vertices $(1,\sqrt 3 )$, $(0, 0)$ and $(2, 0)$ is

If $\omega $ is a cube root of unity, then $(1 + \omega - {\omega ^2})$ $(1 - \omega + {\omega ^2})$ =

The value of $\mathop {\lim }\limits_{x \to 0} {(\cos ax)^{cosec{^2}\ bx}}$ is-