Let A = $\begin{bmatrix} 1 & -2 & 1\\ -2 & 3 & 1\\ 1 & 1 & 5 \end{bmatrix}$. Verify that $(ii)\big(A^{-1}\big)^{-1}$

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This is part 2 of a 2 part question, split as 2 separate questions here.