Question

If A and B are non-zero square matrices of the same order such that AB = 0, then:

• A. adj A = 0 or adj B = 0
• B. | A | = 0 or | B | = 0
• C. adj A = 0 and adj B = 0
• D. | A | = 0 and | B | = 0

Answer 1

Answer: (B)

If A and B are non-zero square matrices of the same order such that
$AB=0\Rightarrow |AB|=0$
$\Rightarrow |A||B|=0$
$\Rightarrow |A|=0$ or $|B|=0$