- #1

- 122

- 0

## Homework Statement

Use LU factorization with partial pivoting for the following set of equations:

3x

_{1}- 2x

_{2}+ x

_{3}= -10

2x

_{1}+ 6x

_{2}- 4x

_{3}= 44

-8x

_{1}- 2x

_{2}+ 5x

_{3}= -26

## The Attempt at a Solution

I made an attempt to solve this problem, but my answer was wrong compared to the book. There was an additional partial pivot after setting elements 21 & 31 equal to zero. I just would like to know why?

The following is what I got for my L and U matrices:

U=

[ -8 -2 5 ]

[ 0 5.5 -3.25]

[ 0 0 1.25]

L=

[1 0 0]

[.25 1 0]

[.775 0.5 1]