A difficult problem about linear algebra.Help

Thread starter tghg
Start date Oct 28, 2006
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The discussion revolves around verifying that if AB is an idempotent matrix, then BA must also be idempotent. An idempotent matrix is defined as one that, when multiplied by itself, yields the same matrix. Participants are encouraged to clarify their understanding of idempotent matrices and identify specific points of confusion. The conversation emphasizes the importance of matrix properties in linear algebra. The problem highlights the interconnectedness of matrix operations and their implications.

Oct 28, 2006

tghg

A difficult problem about linear algebra.Help!

Suppose that A is a m*n matrix，B is a n*m matrix,and AB is a idempotent matrix.
Please verify that BA is also a idempotent matrix.

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Oct 29, 2006

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Do you know what an idempotent matrix is? Where are you getting stuck?

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