Week 8

**Class Notes for Week 8**

**Day 21 - Monday, March 12, 2007**

*Calculator Assignment due today*: Assignment 3 TI-89 Tutorial

**Day 22 - Wednesday, March 14, 2007**

Solving Linear Equations

(L1)3x+4y=12

(L2)-x+5y=-2

A matrix X vector = b vector

3 4 x 12

-1 5 y -2

We used these matrices to solve for x and y.

-x+2y+3z=14

x -z=5

2y+ z=-16

A matrix X vector = b vector

-1 2 3 x 14

1 0 -1 y 5

0 2 1 z -16

We made a 3x3 matrix and a vector in excel to solve for the x vector.

The solution for a linear system: X=A^{-1}b

If the determinent = 0 then the inverse does not exist.

**Day 23 - Friday, March 16, 2007**

Leontif Principle is X = M^{-1}*D

A4 - Leontif I/O is given out.

This assignment involves matrices in excel learned during this week.

page revision: 7, last edited: 28 Sep 2007 13:26