If A is a square matrix of order 3 and $|A|= -2$, then the value of $|-A^{-1}|$ is :
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → $\frac{1}{2}$
$|A|= -2$
$AA^{-1}=I$
so $|A|=\frac{1}{|A^{-1}|}$
so $|-A^{-1}|=-\frac{1}{|A|}=\frac{1}{2}$