Question

What is the determinant of a $1\times 1$ matrix?

Answer 1

The determinant of a $1\times 1$ matrix is the absolute value of the element, present in the matrix itself.

Example:

The determinant of the $1\times 1$ matrix $A=\left[-5\right]$ is,

$\left|A\right|=\left|-5\right|$

$\Rightarrow$$\left|A\right|=-5$