Find the inverse of the matrix (if it exists): $\left[\begin{array}{cc}2 & -2 \\ 4 & 3\end{array}\right]$

Vedclass pdf generator app on play store
Vedclass iOS app on app store
Let $A = \left[\begin{array}{cc}2 & -2 \\ 4 & 3\end{array}\right]$.
We know that the inverse of a matrix $A$ is given by $A^{-1} = \frac{1}{|A|} \text{adj}(A)$,which exists if $|A| \neq 0$.
First,calculate the determinant $|A|$:
$|A| = \left|\begin{array}{cc}2 & -2 \\ 4 & 3\end{array}\right| = (2 \times 3) - (4 \times -2) = 6 + 8 = 14$.
Since $|A| = 14 \neq 0$,the inverse $A^{-1}$ exists.
Next,calculate the adjoint of $A$ (adj $A$):
For a $2 \times 2$ matrix $\left[\begin{array}{cc}a & b \\ c & d\end{array}\right]$,the adjoint is $\left[\begin{array}{cc}d & -b \\ -c & a\end{array}\right]$.
Thus,$\text{adj}(A) = \left[\begin{array}{cc}3 & 2 \\ -4 & 2\end{array}\right]$.
Finally,calculate $A^{-1}$:
$A^{-1} = \frac{1}{14} \left[\begin{array}{cc}3 & 2 \\ -4 & 2\end{array}\right] = \left[\begin{array}{cc}\frac{3}{14} & \frac{2}{14} \\ -\frac{4}{14} & \frac{2}{14}\end{array}\right] = \left[\begin{array}{cc}\frac{3}{14} & \frac{1}{7} \\ -\frac{2}{7} & \frac{1}{7}\end{array}\right]$.

Explore More

Similar Questions

If $A = \begin{bmatrix} 1 & -1 & 1 \\ 0 & 2 & -3 \\ 2 & 1 & 3 \end{bmatrix}$ and $B = \operatorname{adj} A$,$C = 5A$,then $\frac{|\operatorname{adj} B|}{|C|} = $

If $A = \begin{bmatrix} k & 2 \\ -2 & -k \end{bmatrix}$,then $A^{-1}$ does not exist if $k =$

If $A = \begin{bmatrix} 1 & 2 \\ -1 & 4 \end{bmatrix}$ and $A^{-1} = \alpha I + \beta A$,where $\alpha, \beta \in \mathbb{R}$ and $I$ is the identity matrix of order $2$,then $4(\alpha + \beta) = $

If $A$ is a non-singular matrix, then $\operatorname{Adj}\left(A^{-1}\right)=$

If $A = \begin{bmatrix} 3 & 2 \\ 1 & 4 \end{bmatrix}$,then $A(\text{adj } A) = $

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo