Question

If $A=\left[\begin{array}{ccc}1& -1& 1\\ 0& 2& -3\\ 2& 1& 0\end{array}\right],B=(adjA)$ and $C=5A$, then find $\frac{|adjB|}{|C|}$

Answer 1

Answer: 1.00

$|A|=5$
Now $|adjB|=|adj.(adjA)|$
$=|A{|}^4=5^4$
$|C|=|5A|=5^3|A|=5^4$
$\therefore \frac{|adj.B|}{|C|}=1$