Recent content by pol92

You can simply choose a nilpotent non-null matrix, as it's easy to see that the only diagonalizable AND nilpotent matrix is the null one. for example: 01 00

Hello, This is my first post on this forum, and I'm not used to the english mathematical vocabulary, I'll try my best to explain what is my problem. Let (A,+,x) be a ring, ans S be the subset of the indempotents of A, i.e S={x\in A , x^2=x} . I must show that if S is a finite set, then S has...