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

Give the following matrix A = [2 1; 3 2] show that (A^2)-4A+I=0 where I is the 2x2 identity matrix. Hence use your result to deduce the inverse of A.

The attempt at a solution

I can do the show part no problem, but I'm stuck on how to find inverse of A. I multiply both sides of the equation by inverse A and get..

(A^-1)(A^2) - 4A(A^-1) + I(A^-1) = 0(A^-1)

Can you apply index laws on matrices? Any suggestions on what I should do next? Thanks!

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# Homework Help: Matrix Question!

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