If A= [ rr 3 & 1 -1 & 2 ], then A^2+5 A is: - Vidyadip

MCQ

If $A=\left[\begin{array}{rr}3 & 1 \\ -1 & 2\end{array}\right]$, then $A^2+5 A$ is:

A
$\left[\begin{array}{ll}23 & 10 \\ 10 & 13\end{array}\right]$
B
$\left[\begin{array}{ll}10 & 23 \\ 13 & 10\end{array}\right]$
C
$\left[\begin{array}{ll}23 & 10 \\ 10 & 23\end{array}\right]$
✓
$\left[\begin{array}{rr}23 & 10 \\ -10 & 13\end{array}\right]$

✓

Answer

Correct option: D.

$\left[\begin{array}{rr}23 & 10 \\ -10 & 13\end{array}\right]$

(d) $\left[\begin{array}{rr}23 & 10 \\ -10 & 13\end{array}\right]$
Explanation:
$\begin{array}{l}A^2+5 A=A \cdot A+5 A \\ =\left[\begin{array}{rr}3 & 1 \\ -1 & 2\end{array}\right]\left[\begin{array}{rr}3 & 1 \\ -1 & 2\end{array}\right]+5\left[\begin{array}{rr}3 & 1 \\ -1 & 2\end{array}\right] \\ =\left[\begin{array}{rr}8 & 5 \\ -5 & 3\end{array}\right]+\left[\begin{array}{rr}15 & 5 \\ -5 & 10\end{array}\right] \\ =\left[\begin{array}{rr}23 & 10 \\ -10 & 13\end{array}\right]\end{array}$

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 "MCQ" from Matrices→Matrices — all question types→Mathematics STD 10 question papers→ICSE Board STD 10 question papers→ICSE Board question paper generator→

Similar questions

Garima deposited ₹ $500$ per month in a recurring deposit account for 3 years. If the rate of interest is $4 \%$, p.a., then the amount she gets at the time of maturity is :

The median of the data $78,56,22,34,45,54,39,68,54,84$ is:

If $\frac{6}{x}-\frac{2}{x-1}=\frac{1}{x-2}$, then the value(s) of $x$ is/are:

In the given figure, TAS is a tangent to the circle, with centre O , at point A. If $\angle \mathrm{OBA}=32^{\circ}$, then the value of $x$ will be:

If the image of the point $P$ under reflection in the $x$-axis is $(-2,6)$, then coordinates of point $P$ are :

In case of solids, we have volume of the resulting figure $=$ ___________ $\times$ (volume of the given figure), where $k$ is the scale factor.

If the length of the shadow of a pole is equal to its height, then the angle of elevation of Sun is:

If one root of a quadratic equation with rational coefficients is $\frac{3-\sqrt{5}}{2}$, then the other

If $\frac{1}{2}$ is a root of the quadratic equation $4 x^2-4 k x+k+5=0$, then the value of $k$ is

Satyam buys shares at the par value of 20 yielding 10% at the end of a year, then number of shares bought if he receives a dividend of 300 is: