E-CodeLinear system Ax = b from a typed matrix — a TI-89 Titanium program
MSYS89 is a TI-89 BASIC program for the TI-89 Titanium. Type the coefficient matrix (any shape) and the right-hand side: rref decides — the unique solution in exact fractions, INFINITELY MANY with the rank, or NO SOLUTION.
What it asks for and what it shows
It asks for 2 values at its prompts. In the example below it shows X1, X2, X3.
Example run
One of its oracle test cases: “3x3 unique solution”. The inputs are typed in order, and the results are the values the case expects on the screen.
| Step | Value |
|---|---|
| You enter | |
| Input 1 | [[2,1,-1][-3,-1,2][-2,1,2]] |
| Input 2 | {8,-11,-3} |
| The screen shows | |
X1= | 2 |
X2= | 3 |
X3= | -1 |
How it's checked
9 test cases, each checked against an independent method. Replayed key by key on a virtual TI-89 Titanium, they make 41 checks.
How E-Code checks every program
Run it or put it on your calculator
- Open the library in the TI-89 Titanium calculator and pick “Linear system Ax = b from a typed matrix” (MSYS89).
- Put it on your own calculator with a computer and a USB cable, or type it in by hand.
Related programs
- Linear system, exact answers
- Cramer's rule with every determinant
- Quadratic roots, exact when possible
- LU decomposition with pivoting (exact)
- Matrix inverse, exact
All TI-89 Titanium math programs · All TI-89 Titanium programs