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Dragonshade

Member

Registered: 2008-01-16

Posts: 147

Linear algebra

How to prove that

Where

(cof is cofactor)

my book said it follows from 

and

I think it might just be algebra, but still,

George,Y

Member

Registered: 2006-03-12

Posts: 1,379

Re: Linear algebra

Hey Dragonshade, I think you need an example to show how the adj or cof or other things are defined

i.e in this matrix
1 2 3
4 5 6
7 8 9

what are they?

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X'(y-Xβ)=0

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Linear algebra

Hi Dragonshade;

While researching George's post and because I forgot a lot of Gil Strangs book on linear algebra. I came across this page.

http://en.wikipedia.org/wiki/Adjugate

I thought that adj meant adjoint but it looks like its the adjugate. It might help.

Last edited by bobbym (2009-08-22 13:04:36)

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