Hi, I hope this answers your question.

To find an inverse of any square matrix, you can append an identity matrix to the right of your matrix.

Your original matrix:

[5 4 2 4]

[2 3 5 9] = A

[1 0 7 2]

[4 6 2 3]

Changed matrix:

[5 4 2 4 | 1 0 0 0]

[2 3 5 9 | 0 1 0 0] = A | I

[1 0 7 2 | 0 0 1 0]

[4 6 2 3 | 0 0 0 1]

Then, row-reduce the the big matrix to get an identity matrix on the left. After that, the transformed matrix on the right side is the inverse of the original matrix.

Note, matrix has an inverse only if its determinant is non-zero,

|A| not= 0.

This method is based on the obvious fact that if you multiply a matrix by its inverse, you get an identity matrix.

I haven’t done that myself, but I think that it’s not that hard to find an algorithm for this procedure.

P.S. If you want to know how to find the determinant of a matrix, post a message.

[This message has been edited by Aster (edited 09-07-2000).]