MathDB

A5

Part of 1990 Putnam

Problems(1)

Square matrices A and B

Source: Putnam 1990 A5

7/12/2013
If A\mathbf{A} and B\mathbf{B} are square matrices of the same size such that ABAB=0\mathbf{ABAB}=\mathbf{0}, does it follow that BABA=0\mathbf{BABA}=\mathbf{0}.
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