Adjugate matrix

Minor Cofactor 余子式 代数余子式

In linear algebra, the adjugate or classical adjoint of a square matrix is the transpose of its cofactor matrix.

The adjugate of A is the transpose of the cofactor matrix C of A,

$\mathbf{A}=\left[\begin{array}{cc}a& b\\ c& d\end{array}\right]$ → $\mathrm{adj}(\mathbf{A})=\left[\begin{array}{cc}d& -b\\ -c& a\end{array}\right]$