Science:Math Exam Resources/Courses/MATH152/April 2022/Question A19/Hint 1

The inverse $A^{-1}$ is a matrix that satisfies the equation $AA^{-1}=\mathrm {Id}$. Recall that you can solve this (system of) equation(s) by using row operations on an augmented matrix. See section 4.5 of the notes for MATH 152, |linked here.