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Author Maths problem: Guassian Elimination - Help!
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From: ...whatever psycho!!!
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Posted: 2009-03-15 18:36
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Doin a bit of maths coureswork, done every question except this 1!

[U]1. The problem statement, all variables and given/known data[/U]
I have been given the 3 following simultaneous equations



and the question is:
"(a) Solve the equations using Gaussian elimination, showing all your working."

fairly simple topic i know, but i cant get the answer :/

[U]2. The attempt at a solution[/U]
Had a few attempts at it.. heres one of them:

Heres my augmented matrix:



I switched Row 1 (R1) with Row 2 (R2)



any from there i can work out x1, x2, x3 etc... but i keep getting reidiculous numbers. And when i check them in the 1st set of equations given, they obviously come out to be wrong.

I.e for this attempt i get

x3 = 517/210
x2 = -2297/1230
x1 = -19.408

What am I doing wrong? Any help is much appreciated
Thanks
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From: ...whatever psycho!!!
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Posted: 2009-03-15 21:51
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Nevermind, worked out my mistake

Solved it
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arien617
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Posted: 2009-03-15 22:17
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Is this A Level, or Uni work?
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From: ...whatever psycho!!!
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Posted: 2009-03-15 22:24
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well it was covered in a level, at uni now tho...

quite a simple problem in the scheme of things, but i kept makin silly little mistakes!
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