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For a 1x1 matrix $[a]$, the determinant is simply the scalar entry $a$ itself.

Conditions: The matrix is of size 1x1.; The single entry is $a$.

For a 1x1 matrix $[a]$, the determinant is simply the scalar entry $a$ itself.

Conditions: The matrix is of size 1x1.; The single entry is $a$.

No, the determinant is a scalar value that can be positive, zero, or negative. It is explicitly not a matrix absolute value, despite the notation $|A|$ sometimes being used.

Conditions: The object is a square matrix.; The notation $|A|$ or $\det(A)$ is being interpreted.

No, the determinant is a scalar value that can be positive, zero, or negative. It is explicitly not a matrix absolute value, despite the notation $|A|$ sometimes being used.

Conditions: The object is a square matrix.; The notation $|A|$ or $\det(A)$ is being interpreted.