Download App

STD 12 - 3 and 4 . determinant and metrices — Mathematics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceMathematicsSTD 12 - 3 and 4 . determinant and metrices1 Mark
MCQ
If $A = \left[ {\begin{array}{*{20}{c}}2&3\\4&6\end{array}} \right]$, then ${A^{ - 1}}$=
  • A
    $\left[ {\begin{array}{*{20}{c}}1&2\\{ - 3/2}&3\end{array}} \right]$
  • B
    $\left[ {\begin{array}{*{20}{c}}2&{ - 3}\\4&6\end{array}} \right]$
  • C
    $\left[ {\begin{array}{*{20}{c}}{ - 2}&4\\{ - 3}&6\end{array}} \right]$
  • ✓
    Does not exist
✓

Answer

Correct option: D.
Does not exist
d
(d) Given,$A = \left[ {\begin{array}{*{20}{c}}2&3\\4&6\end{array}} \right]$,

we know that ${A^{ - 1}} = \frac{{adj.A}}{{|A|}}$.

Therefore, $|A|\,\, = \,\,[12 - 12] = 0.$

Since $|A|$ is zero,

therefore inverse of $A$  does not exist.

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 STD 12 - 3 and 4 . determinant and metrices→STD 12 - 3 and 4 . determinant and metrices — all question types→Mathematics STD 12 Science question papers→CBSE Board STD 12 Science question papers→CBSE Board question paper generator→

Similar questions

$\int|\text{x}|\text{dx}$ is equal to:
→
The order of the single matrix obtained from
$
\left[\begin{array}{rr}
1 & -1 \\
0 & 2 \\
2 & 3
\end{array}\right]\left\{\left[\begin{array}{rrr}
-1 & 0 & 2 \\
2 & 0 & 1
\end{array}\right]-\left[\begin{array}{lll}
0 & 1 & 23 \\
1 & 0 & 21
\end{array}\right]\right\} \text { is }
$
→
If $x \in [0, 1]$, then the number of solution $(s)$ of the equation $2[cos^{-1}x] + 6[sgn(sinx)] = 3$ is (where $[.]$ denotes greatest integer function and sgn $(x)$ denotes signum function of $x$)-
→
The area of a parallelogram whose adjacent sides are given by the vectors $i + 2j + 3k$ and $ - 3i - 2j + k$ (in square unit) is
→
A rifleman is firing at a distant target and has only $10\%$ chance of hiting it. the least number of round he must fire in order to have more than $50\%$ chance of hitting it at least once is :
→
If $\int \operatorname{cosec}^5 x d x=\alpha \cot x \operatorname{cosec} x\left(\operatorname{cosec}^2 x+\frac{3}{2}\right)+\beta \log _e\left|\tan \frac{x}{2}\right|+C$ where $\alpha, \beta \in \mathbb{R}$ and $\mathrm{C}$ is constant of integration , then the value of $8(\alpha+\beta)$ equals....................
→
$\int_{}^{} {{e^{{x^2}}}x\;dx} $ is equal to
→
Choose the correct answer from the given four options.If $A$ and $B$ are two matrices of the order $3 \times m$ and $3 \times n,$ respectively and $m = n$, then order of matrix $(5A – 2B)$ is:
→
Let A and B be two events. If $\text{P(A)}=0.2,\text{P(B)}=0.4,\text{P}(\text{A}\cup\text{B})=0.6$ then P(A|B) is equal to
→
The derivative of $x^{2 x}$ w.r.t. $x$ is
→