If A=(1234)A = \begin{pmatrix} 1 & 2 \\ 3 & 4 \end{pmatrix}A=(1324), what is det(A−1)\det(A^{-1})det(A−1)?
−12-\frac{1}{2}−21
−2-2−2
12\frac{1}{2}21
2