What must be the matrix X if 2X + [ * 20 c 1&2 3&4 ] = [ * 20 c 3… - Vidyadip

MCQ

What must be the matrix $X$ if $2X + \left[ {\begin{array}{*{20}{c}}1&2\\3&4\end{array}} \right] = \left[ {\begin{array}{*{20}{c}}3&8\\7&2\end{array}} \right]$

✓
$\left[ {\begin{array}{*{20}{c}}1&3\\2&{ - 1}\end{array}} \right]$
B
$\left[ {\begin{array}{*{20}{c}}1&{ - 3}\\2&{ - 1}\end{array}} \right]$
C
$\left[ {\begin{array}{*{20}{c}}2&6\\4&{ - 2}\end{array}} \right]$
D
$\left[ {\begin{array}{*{20}{c}}2&{ - 6}\\4&{ - 2}\end{array}} \right]$

✓

Answer

Correct option: A.

$\left[ {\begin{array}{*{20}{c}}1&3\\2&{ - 1}\end{array}} \right]$

a
(a) $2X\, = \left[ {\begin{array}{*{20}{c}}3&8\\7&2\end{array}} \right] - \left[ {\begin{array}{*{20}{c}}1&2\\3&4\end{array}} \right]$
$2X = \left[ {\begin{array}{*{20}{c}}2&6\\4&{ - 2}\end{array}} \right] \Rightarrow X = \left[ {\begin{array}{*{20}{c}}1&3\\2&{ - 1}\end{array}} \right]$.

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

More "M.C.Q (1 Marks)" from 3 and 4 . determinant and metrices→3 and 4 . determinant and metrices — all question types→Maths STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

For the function $f(x) = {x^2} - 6x + 8,2 \le x \le 4$, the value of $x$ for which $f'(x)$ vanishes, is

Let f(x) = x³ be a function with domain {0, 1, 2, 3}. Then domain of f^-1 is:

{3, 2, 1, 0}
{0, -1, -2, -3}
{0, 1, 8, 27}
{0, -1, -8, -27}

If $y = {2^{1/{{\log }_x}4}}$, then $ x$ is equal to

If points $\text{A}(60\hat{\text{i}}+3\hat{\text{j}}),\ \text{B}(40\hat{\text{i}}-8\hat{\text{j}})$ and $\text{C}(\text{a}\hat{\text{i}}+52\hat{\text{j}})$ are collinear, then a is equal to,

40
-40
20
-20

The determinant $\left|\begin{array}{ccc}y+k & y & y \\ y & y+k & y \\ y & y & y+k\end{array}\right|$ is equal to

The xy-plane divided the line joining the point (-1, 3, 4) and (2, -5, 6)

Internally in the ratio 2 : 3
Externally in the ratio 2 : 3
Internally in the ratio 3 : 2
Externally in the ratio 3 : 2

The sum of two non-zero numbers is $4$ . The minimum value of the sum of their reciprocals is

Given that the fuel cost per hour is $k$ times the square of the speed the train generates in $km / h$, the value of $k$ is

Let $A=\left[\begin{array}{l}a_{1} \\ a_{2}\end{array}\right]$ and $B=\left[\begin{array}{l}b_{1} \\ b_{2}\end{array}\right]$ be two $2 \times 1$ matrices with real entries such that $A = XB,$

where $X=\frac{1}{\sqrt{3}}\left[\begin{array}{cc}1 & -1 \\ 1 & k\end{array}\right],$ and $k \in R$. If $a _{1}^{2}+ a _{2}^{2}=\frac{2}{3}\left( b _{1}^{2}+ b _{2}^{2}\right)$ and $\left( k ^{2}+1\right) b _{2}^{2} \neq-2 b _{1} b _{2}$ then the value of $k$ is ....... .

If a particle is moving in a straight line. In $t$ time, it will cover $x$ distance according to $x=2 t^2-5 t+$ 1 then find the velocity after 5 sec .