If A and B are idempotent(A=A^2) and AB=BA, prove that AB is idempotent.(adsbygoogle = window.adsbygoogle || []).push({});

this is what i got so far.

AB=BA

AB=B^(2)A^(2)

AB=(BA)^(2)

this is where I get stuck.

Do A and B have inverses? if so, why?

should I be thinking about inverses or is there another way of approaching this problem?

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# Idempotent proof

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