I'm studying for a test and I got stuck here. Let A be the matrix: 3..1 2..1 In each part find p(a). a) p(x)=x-2 The answer is: 1..1 2..-1 The only way I can see this happen is that we take the numbers on the diagonal and pluck it in p(x). So... x-2=3-2=1 x-2=1-2=-1 Leaving the others alone, we get. 1..1 2..-1 The problem is, I know this is WRONG. This method does not work for b) and c), which are polynomials of higher degrees. The inverse is: 1..-1 -2..3 I still can see a solution pattern. I tried to relate to the chapter, but no luck. Any help is appreciated.