CUET Preparation Today
CUET
-- Applied Mathematics - Section B2
Algebra
If A and b are square matrices of order 3 such that $|A|= -1, |B|=3, $ then $|3\, AB|$ equals
-9
-81
-27
81
The correct answer is option (1) : -9
We have, $|A|= -1, |B|= 3$
$∴|3\, AB|= 3 |A||B|=3×-1×3=-9$
