\[A=\begin{bmatrix}1 & -1 & 2\\-5 & 7 & -11\\-2 & 3 &-5\end{bmatrix}\]
\[A^{-1}=\begin{bmatrix}\answer {2} & \answer {-1} & \answer {3}\\\answer {3} & \answer {1} & \answer {-1}\\\answer {1} & \answer {1} &\answer {-2}\end{bmatrix}\]