If $A$ is a square matrix with $|A| = 3$ and order $n = 3$, then $|\operatorname{adj}(A)|$ equals:
A$3$
B$9$
C$27$
D$1/3$
Answer & Solution
Correct answer: B. $9$
$|\operatorname{adj}(A)| = |A|^{n - 1}$.
With $|A| = 3$ and $n = 3$, this gives $|\operatorname{adj}(A)| = 3^{3 - 1} = 3^2 = 9$.
Keep practising Number Systems
Browse all Number Systems questions for CBSE Class 9, or explore more Mathematics topics.
Related questions
The set of rational numbers Q is CLOSED under all of the following operations EXCEPT:The set of INTEGERS is denoted by the symbol:How many rational numbers are there between any two distinct rationals?Compute (-3/5) × (10/9):Which of the following can be written as a rational p/q in lowest terms with q having ONLYThe difference between two positive integers is 63, and they are in the ratio 2:5. The smaSalil's mother is currently three times Salil's age. After 5 years, their ages will add upFind the value of the linear polynomial 5x − 3 at x = −1: