Question

If $A$ is a $3$$\times$$3$ matrix, then what will be the value of $det\left(adjA\right)$ if $det\left(A\right)=7$.

Answer 1

We know

$|adjA|=|A{|}^{n-1}$

Where n is no. of matrix

Given n=3 & |A|=7

So,

$|adjA|=|A{|}^2=(7{)}^2=49$

$|adjA|=49$