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#1 2006-01-10 02:12:23

Ricardo
Guest

Um sistema

|3x+2y-2z=1
|2x+y+4z=0
|5x+3y-5z=2
This here is a system. Please, can you help me solve it? Thank you.

#2 2006-01-10 03:51:52

seerj
Member
Registered: 2005-12-21
Posts: 42

Re: Um sistema

If Ididn't wrong the values are:

x=3/7
y=-2/7
z=-1/7

Tell me if they are right please.

Last edited by seerj (2006-01-10 03:52:16)

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#3 2006-01-10 04:02:04

seerj
Member
Registered: 2005-12-21
Posts: 42

Re: Um sistema

Yes they are right.
So u can create a matrix associated to the system. Where in the left side there are the values of the variables and on the right side there are the known values.

| 3  2  -2 | 1|                                                                             |3      2      -2      |  1    |
| 2  1   4 | 0|  by using gauss method u'll have a matrix like this    |0   -1/3    16/3    | -2/3|
| 5  3  -5 | 2|                                                                             |0      0       -7     | 1     |

so u have to create a new system with the new values

| 3x +2y -2z=1
|     -1/3y +16/3z=-2/3
|                   -7z=1

and ull have that   z= -1/7   y=-2/7   x=3/7


Tell me if u need help

PS: I used the Gauss-Jordan algorithm -->http://mathworld.wolfram.com/Gauss-JordanElimination.html

Last edited by seerj (2006-01-10 04:04:11)

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#4 2006-01-15 01:18:15

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,908

Re: Um sistema

Correct! this is the exact solution!


IPBLE:  Increasing Performance By Lowering Expectations.

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