If A = [ ll 3 & 2 7 & 5 ], B = [ ll 6 & 7 8 & 9 ], then adj( AB )… - Vidyadip

MCQ

If $A =\left[\begin{array}{ll}3 & 2 \\ 7 & 5\end{array}\right], B =\left[\begin{array}{ll}6 & 7 \\ 8 & 9\end{array}\right]$, then $\operatorname{adj}( AB )$ is equal to

✓
$\left[\begin{array}{cc}94 & -39 \\ -82 & 34\end{array}\right]$
B
$\left[\begin{array}{ll}94 & -39 \\ 82 & -34\end{array}\right]$
C
$\left[\begin{array}{cc}94 & -82 \\ -39 & 34\end{array}\right]$
D
$\left[\begin{array}{cc}-94 & -39 \\ 82 & 34\end{array}\right]$

✓

Answer

Correct option: A.

$\left[\begin{array}{cc}94 & -39 \\ -82 & 34\end{array}\right]$

(A) $AB =\left[\begin{array}{ll}34 & 39 \\ 82 & 94\end{array}\right] \Rightarrow \operatorname{adj}( AB )=\left[\begin{array}{cc}94 & -39 \\ -82 & 34\end{array}\right]$

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 "MCQ" from Matrics→Matrics — all question types→Maths STD 12 Science question papers→Maharashtra Board STD 12 Science question papers→Maharashtra Board question paper generator→

Similar questions

The area bounded by the parabola $y^2=x$ along the $X$-axis and the lines $x=0, x=2$ is ____ sq.units

The matrix $\left[\begin{array}{lll}1 & a & 2 \\ 1 & 2 & 5 \\ 2 & 1 & 1\end{array}\right]$ is not invertible, if ' $a$ ' has the value

If $\text{x}=\text{f}(\text{t})\cos\text{t}-\text{f}(\text{t})\sin\text{t}\ \text{and}\ \text{y}=\text{f}(\text{t})\sin\text{t}+\text{f}(\text{t})\cos\text{t},$ then $\Big(\frac{\text{dx}}{\text{dt}}\Big)^2+\Big(\frac{\text{dy}}{\text{dt}}\Big)^2=$

The angle between the lines represented by the equation $a x^2+x y+b y^2=0$ will be $45^{\circ}$, if

If $\sin^{-1}\Big(\frac{\text{x}^2-\text{y}^2}{\text{x}^2+\text{y}^2}\Big)=\log\text{a}$ then $\frac{\text{dy}}{\text{dx}}$ is equal to:

If $S = [S_{ij}]$ is a scalar matrix such that $S_{ij} = k$ and $A$ is a square matrix of the same order, then $AS = SA = ?$

The value of $\int_0^1 \frac{x^4+1}{x^2+1} d x$ is

Find the equation of the perpendicular drawn from the point $(2,4,-1)$ to the line $x+5=\frac{1}{4}(y+3)=-\frac{1}{9}(z-6)$ and obtain the co-ordinates of the foot of this perpendicular

$\int[\sin (\log x)+\cos (\log x)] \cdot d x=$

Let $f (x)=x-[x]$, for every real number $x$, where $[x]$ is integral part of $x$.
Then, $\int_{-1}^1 f(x) d x$ is