CUET Preparation Today
CUET
-- Mathematics - Section B1
Matrices
If A is a square matrix of order 3 and $|A| = -3$, then value of $|2AA^T|$ is
-36
-72
72
36
$|A| = -3$
so, $|2AA^T|=2^3|A||A^T|$ $[∵|A|=|A^T|=-3]$
$=8×(-3)×(-3)$
$=72$
