If A is a matrix of order 3, and |adj A| = 25, then what is the value of |A|?
Answer & explanation
Correct answer: option 3
| adj A| = \( { |A| }^{ n-1 } \), where n is the order of the matrix
|adj A| = \( { |A| }^{ 3-1 } \)
25 = \( { |A| }^{ 2 } \)
|A| = 5 or -5