Cofactor/Examples/Arbitrary Example 1

Example of Cofactor
Let $D$ be the determinant defined as:


 * $D = \begin {vmatrix} 1 & 2 & 3 \\ 4 & 5 & 6 \\ 7 & 8 & 9 \end {vmatrix}$

Then the cofactor of $2$ is defined as: