Given matrix is,
A=[ 2 −2 4 3 ]
The determinant of the given matrix is,
| A |=2×3−( −2 )×4 =6+8 =14
Cofactor of a 11 is,
A 11 = ( −1 ) 1+1 ( 3 ) =3
Cofactor of a 12 is,
A 12 = ( −1 ) 1+2 ( 4 ) =−4
Cofactor of a 21 is,
A 21 = ( −1 ) 2+1 ( −2 ) =2
Cofactor of a 22 is,
A 22 = ( −1 ) 2+2 ( 2 ) =2
So, the adjoint of the given matrix is,
adjA=[ A 11 A 21 A 12 A 22 ] =[ 3 2 −4 2 ]
The inverse of the given matrix is,
A −1 = 1 | A | adjA = 1 14 [ 3 2 −4 2 ]