Question

If A is a singular matrix, then A (adj A) is a

• A. scalar matrix
• B. zero matrix
• C. identity matrix
• D. orthogonal matrix

Answer 1

The correct option is B zero matrix

Given $A$ is a singular matrix.
$\Rightarrow |A|=0$
$A\left(adjA\right)=|A|I=0I=O$
$\therefore A\left(adjA\right)$ is a zero matrix.
Hence, option B.