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Definition D5941
Real square matrix cofactor

Let $A \in \mathbb{R}^{N \times N}$ be a D6160: Real square matrix such that
 (i) $N \in \{ 2, 3, 4, \ldots \}$ is a D5094: Positive integer (ii) $n, m \in \{ 1, 2, \ldots, N \}$ are each a D5094: Positive integer (iii) $B \in \mathbb{R}^{(N - 1) \times (N - 1)}$ is a D5939: Real matrix standard submatrix for $A$ with respect to $(n, m)$
The cofactor for $A$ with respect to $(n, m)$ is the D993: Real number $$(-1)^{n + m} \text{Det} B$$
Children
 ▶ Real cofactor matrix
Results
 ▶ Cofactor partition for the determinant of a 3-by-3 real square matrix ▶ Cofactor partition for the determinant of a real square matrix