HP 39G User Manual page 186

Reduced-Row
Echelon Form
12-14
The following set of equations
can be written as the augmented matrix
which can then stored as a
3 4 real matrix in M1.
You can use the RREF
function to change this to
reduced row echelon form,
storing it as M2 for
convenience.
The reduced row echelon
matrix gives the solution to
the linear equation in the
forth column.
An advantage of using the RREF function is that it will also
work with inconsistent matrices resulting from systems of
equations which have no solution or infinite solutions.
For example, the following set of equations has an infinite
number of solutions:
x + y z – = 5
2x y – = 7
x 2y – + z = 2
The final row of zeros in the
reduced–row echelon form of
the augmented matrix
indicates an inconsistency.
x 2y – + 3z = 14
2x + y z – = – 3
4x – 2y + 2z = 14
1 2 – 3 14
2 1 1 – 3 –
4 2 – 2 14
Matrices