Question

The cofactor \(C_{ij}\) (or \(A_{ij}\)) of \(a_{ij}\) is which quantity?

Options

• \[C_{ij}=(-1)^{i+j}M_{ij}\]

• \[C_{ij}=(-1)^{ij}M_{ij}\]

• \[C_{ij}=(-1)^{i-j}M_{ij}\]

• \[C_{ij}=M_{ij}\]

Answer 1

A cofactor is obtained by multiplying the minor by the sign factor \((-1)^{i+j}\). Thus, \(C_{ij}\), also written as \(A_{ij}\), equals \((-1)^{i+j}M_{ij}\).