CUET Preparation Today
CUET
-- Mathematics - Section A
Matrices
If A is a square matrix such that $A^2=A,$ then |A| equals
0 or 2
0 or 1
0 or -1
-1 or -2
The correct answer is Option (2) → 0 or 1
$A^2=A$
so $|AA|=|A|$
$|A|^2=|A|$
$|A|=0,1$
