How to do an elimination procedure to represent the solution (matrix)

1 view (last 30 days)
Apply the elimination procedure until you reach a matrix that represents
the solution (identity matrix + column with the values for x1, x2 and x3,
see slide 1.1-14 from Linear Algebra). Include each step (code needed)
in the report and explain the process.
The polynomials:
x1 - 2x2 + x3 = 0
2x2 - 8x3 = 8
-4x1 + 5x2 +9x3 = -9

Accepted Answer

Sam Chak
Sam Chak on 17 Apr 2022
Can you show the slides and elimination formulas? Otherwise, I think this elimination procedure:
A = [1 -2 1;
0 2 -8;
-4 5 9]
b = [0; 8; -9]
[L, U, P] = lu(A)
y = L\(P*b)
x = U\y
  3 Comments
Torsten
Torsten on 18 Apr 2022
Edited: Torsten on 18 Apr 2022
y = L\(P*b)
is forward substitution,
x = U\y
is back substitution.
Be careful with the direction of the slash - above, you did it wrong.

Sign in to comment.

More Answers (0)

Categories

Find more on Polynomials in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by