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#1 2007-10-11 00:48:52

freddogtgj
Member
Registered: 2006-12-02
Posts: 54

Linear Algebra- Square matrices

I have this question that's causing some confusion:
Let A and B be square matrices of the same size. Show that

(A+B)(A-B)=A²-B²

if and only if A and B commute.

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#2 2007-10-11 01:06:44

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: Linear Algebra- Square matrices

Last edited by JaneFairfax (2007-10-11 01:08:30)

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#3 2007-10-11 02:57:32

freddogtgj
Member
Registered: 2006-12-02
Posts: 54

Re: Linear Algebra- Square matrices

Thanks appreciate it!

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