Adjoint Matrix can be found by forming the cofactor matrix and then finding its transpose. Adjoint Matrix is defined as follows:

If $A_{n\times n}$= $\left [ a_{ij} \right ]_{n\times n}$, then adj A = $\left [ c_{ij} \right ]_{n\times n}^T$, where Cij = (-1)i+j Mij and Mij indicates minors of the elements.

In order to find the adjoint of a matrix A, which is a square matrix of order nxn, we have to follow procedure given below:

  • Calculate cofactors of each element of the matrix using minors.
  • Form cofactor matrix from the calculated cofactors.
  • Find transpose matrix of the cofactor matrix.