I'm writing functions for my matrix class that will find the inverse of a matrix and will put a system in row reduced echelon form.

I have a pretty good idea of how I'll manage with forward elimination - create an elimination matrix, like so:

|1 0 0|

|-2 1 0|

|0 0 1|

and multiply it by the matrix, which would subtract twice the first row from the second row.

BUT to do rref or to find an inverse, I must be able to do BACKWARDS elimination - I understand the concept perfectly on paper, but I would like to be able to put it in terms of an elimination matrix for my program. i.e, whatelimination matrixwould you need to change (1,2) in the following matrix into a 0:

|2 2 0|

|0 3 0|

|0 0 5|

Or is there no elimination matrix that does this (perhaps thats why our teacher didn't say what it was) and I must just write a function to do the actual multiplying of a row and subtracting it from another row?

Thanks