On idempotency of linear combinations of two commute idempotent matrices

$P_1$, ve $P_2$ komutatif idempotent matrislerinin lineer kombinasyonunun da bir idempotent matris olduğu tüm durumları karakterize etme probleminin tanı bir çözümü ortaya konulmaktadır. Ayrıca, bu çalışmada ele alınan idempotentlik probleminin bir istatistiksel yorumu da verilmektedir.

A complete solution is established to the problem of characterizing all situations, where a linear combination of two commute idempotent matrices $P_1$, and $P_2$ is also an idempotent matrix. A statistical interpretation of the idempotency problem considered in this note is aiso pointed out.

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