Question

If A is a square matrix of order 3 such that $|A|=2$ then the value of $|(adj{A}^{-1}{)}^{-1}|$ is ___ .

Answer 1

$|adj.A^{-1}|=|A^{-1}{|}^2=\frac{1}{|A{|}^2}|(adj{A}^{-1}{)}^{-1}|=\frac{1}{|adj{A}^{-1}|}=|A{|}^2=2^2=4$