1.
Let A={aij}A = \{a_{ij}\} be a 3×33 \times 3 matrix, where
aij={(1)jiif i<j,2if i=j,(1)i+jif i>j.a_{ij} = \begin{cases} (-1)^{j-i} & \text{if } i < j, \\ 2 & \text{if } i = j, \\ (-1)^{i+j} & \text{if } i > j. \end{cases}

Then det(3Adj(2A1))\det\left( 3\, \text{Adj}(2 A^{-1}) \right) is equal to: