Adjugate Matrix Calculator

The calculator will find the adjugate (adjoint, adjunct) matrix of the given square matrix, with steps shown.

If the calculator did not compute something or you have identified an error, or you have a suggestion/feedback, please write it in the comments below.

Your Input

Find the adjugate matrix of $$$\left[\begin{array}{ccc}1 & 2 & 3\\4 & 5 & 6\\7 & 8 & 9\end{array}\right]$$$.

Solution

The adjugate, classical adjoint, or adjunct of a square matrix is the transpose of its cofactor matrix.

The cofactor matrix is $$$\left[\begin{array}{ccc}-3 & 6 & -3\\6 & -12 & 6\\-3 & 6 & -3\end{array}\right]$$$ (for steps, see cofactor matrix calculator).

The transpose of the cofactor matrix is $$$\left[\begin{array}{ccc}-3 & 6 & -3\\6 & -12 & 6\\-3 & 6 & -3\end{array}\right]$$$ (for steps, see matrix transpose calculator).

Answer

The adjugate matrix is $$$\left[\begin{array}{ccc}-3 & 6 & -3\\6 & -12 & 6\\-3 & 6 & -3\end{array}\right]$$$A.