(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Show that [tex] (I-A)^{-1} = I + A + A^2 + A^3 [/tex] if [tex]A^4=0[/tex]

3. The attempt at a solution

I found at Google Books some kind of formula for it:

http://books.google.com/books?id=UQ...PA44#v=onepage&q=inverse sum matrices&f=false

However, I think I should develop some kind of series for it using I = A(A^-1), I tried but I haven't been successful...

Thanks in advance.

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# Homework Help: Linear algebra: inverse of the sum of two matrices

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