Question
Mathematics Question on Determinants
If A and B are square matrices of order 3, such that ∣A∣=−1,∣B∣=3 then the determinant of 3 AB is equal to
A
-9
B
-27
C
-81
D
81
Answer
-81
Explanation
Solution
∣3AB∣=33∣A∣B∣ =27(−1)(3)=−81.
If A and B are square matrices of order 3, such that ∣A∣=−1,∣B∣=3 then the determinant of 3 AB is equal to
-9
-27
-81
81
-81
∣3AB∣=33∣A∣B∣ =27(−1)(3)=−81.