The inverse of matrix $\begin{bmatrix} 5 & 2 \\ 7 & 3 \end{bmatrix}$ is-

Explanation

Let, $A = \begin{bmatrix} 5 } 5 & 2 \\ 7 7 & 3 \end{bmatrix}$ ∴ Adj $A = \begin{bmatrix} 3 3 & -2 \\ -7 \\ -7 & 5 \end{bmatrix}$ and $|A| = 3 \times 5 - 7 \times 2$ $= 15 - 14$ $= 1$ ∴ $A^{-1} = \frac{Adj A}{|A|} = \frac{1}{1} \begin{bmatrix} 3 3 & -2 \\ -7 7 & 5 \end{bmatrix}$ $= \begin{bmatrix} 3 3 & -2 \\ -7 & 5 \end{bmatrix}$ ## Page 45