In the following we assume we have a square matrix (m=n). The determinant of a matrix A will be denoted by det(A) or |A|.
Assuming A is an arbitrary 2x2 matrix A, where the elements are given by:
then the determinant of a this matrix is as follows:
The determinant of a 3x3 matrix is a little more tricky and is found as follows ( for this case assume A is an arbitrary 3x3 matrix A, where the elements are given below)
then the determinant of a this matrix is as follows: