MathDB
Romania District Olympiad 2011 - Grade XI

Source:

March 12, 2011
linear algebralinear algebra unsolved

Problem Statement

Let A,BM2(C)A,B\in \mathcal{M}_2(\mathbb{C}) two non-zero matrices such that AB+BA=O2AB+BA=O_2 and det(A+B)=0\det(A+B)=0. Prove AA and BB have null traces.