Question

If A is a 3-rowed square matrix and │A│=5 then │adj A│=? 

A. 5 

B. 25 

C. 125 

D. none of these

Answer 1

The property states that │adj A│= │A│^n-1 

Here n= 3 and │A│=5 

│adj A│= │5|^3-1 

= │5│² 

= 25