Question

Suppose $A$ is a $4\times 4$ matrix such that $|A|=4$, find $|adjA|$.

Answer 1

$Aisa4\times 4matrixand\left|A\right|=4$

$\left|adjA\right|={\left|A\right|}^{n-1}={\left|A\right|}^3$

$Hence\left|adjA\right|=64$