Question

Linear Algebra,

can someone please explain to me how he got this answer http://screencast.com/t/pKxON8wZYQe

Answer 1

How he got the y1, y2, y3?

Answer 2

yes

Answer 3

It seems pretty straightforward...

x - y = 1
y - z = 1
x - z = 1

You just gotta find numbers to multiply that'll allow you to add the equations so the left side adds up to zero, and the right to 1.

Answer 4

If you add the first two equations as is, ie multiplying them by 1, that cancels off y. Then you gotta cancel off x and z with the last.

Answer 5

yes but how do I find 1 1 - 1

Answer 6

do I find it with a glance

Answer 7

and why is it called y? is it the y used at y^t * b = 1

Answer 8

I guess so, by trial and error/eyeballing. Like I said with the first two you can add them as is. That's multiplying them by 1. Then just figure out that you have to multiply the last by -1

Answer 9

before starting the question it does some introduction to fredholms alternative, what does that have to do with anything ?

Answer 10

I'm not really sure, it's been a while since I took linear algebra.

Answer 11

But to me it seems like unnecessary crap.

Answer 12

yea it looks so confusing indeed :S

Answer 13

Yeah, way more confusing than the actual given equations and finding the y1, y2, y3 :/

Answer 14

I pretty much ignored it haha, and just answered the easy part