यदि A= [ ll 1 & 2 3 & 4 ] हो, तो A ^ -1 का मान होगा-

MCQ

यदि $A=\left[\begin{array}{ll}1 & 2 \\ 3 & 4\end{array}\right]$ हो, तो $A ^{-1}$ का मान होगा-

A
$\left[\begin{array}{ll}4 & 2 \\ 3 & 1\end{array}\right]$
✓
$\left[\begin{array}{cc}-2 & 1 \\ \frac{3}{2} & -1 / 2\end{array}\right]$
C
$\left[\begin{array}{cc}4 & -3 \\ 2 & 1\end{array}\right]$
D
$\left[\begin{array}{ll}-4 & 3 \\ -2 & 1\end{array}\right]$

✓

Answer

Correct option: B.

$\left[\begin{array}{cc}-2 & 1 \\ \frac{3}{2} & -1 / 2\end{array}\right]$

(B) $\left[\begin{array}{cc}-2 & 1 \\ \frac{3}{2} & -1 / 2\end{array}\right]$
$-A_{11}=4, A_{12}=-3, A_{21}=-2, A_{22}=1$
$\operatorname{adj} A =\left[\begin{array}{cc}4 & -3 \\ -2 & 1\end{array}\right]^{\prime}=\left[\begin{array}{cc}4 & -2 \\ -3 & 1\end{array}\right]$
$|A|=4-6=-2 \neq 0$
$A ^{-1}=\frac{\operatorname{adj} A }{| A |}=\frac{-1}{2}\left[\begin{array}{cc}4 & -2 \\ -3 & 1\end{array}\right]=\left[\begin{array}{cc}-2 & 1 \\ \frac{3}{2} & -1 / 2\end{array}\right]$
अतः सही विकल्प (B) है।

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 सारणिक→सारणिक — all question types→गणित कक्षा 12 साइन्स question papers→CBSE Board कक्षा 12 साइन्स question papers→CBSE Board question paper generator→

सारणिक — गणित कक्षा 12 साइन्स — Question

Answer

Need a full question paper?

Explore more

Similar questions