Understanding N in Jordan Block Matrix

Wildcat
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Homework Statement



Let J be any Jordan block, i.e. J =λI + N where N is the matrix whose (i,j) entry is δi,j-1.
PJ(λ) is J's characteristic polynomial. Show that PJ(J)=0.

Homework Equations





The Attempt at a Solution



I don't understand what this part of the question means → N is the matrix whose (i,j) entry is δi,j-1. Can someone explain? Does it mean that for example the (2,2) entry of N would be the (2,1) entry of J which would be 0? Making the diagonal entries of N all =0??
 
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Wildcat said:

Homework Statement



Let J be any Jordan block, i.e. J =λI + N where N is the matrix whose (i,j) entry is δi,j-1.
PJ(λ) is J's characteristic polynomial. Show that PJ(J)=0.

Homework Equations





The Attempt at a Solution



I don't understand what this part of the question means → N is the matrix whose (i,j) entry is δi,j-1. Can someone explain? Does it mean that for example the (2,2) entry of N would be the (2,1) entry of J which would be 0? Making the diagonal entries of N all =0??


I don't know how to close threads, but while I was waiting for a reply i figured it out!
 
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