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If A and B are square matrices of order n, such that AB = A and BA = B, then A2A^2 =

Solution

✅ Correct Option: 1

Using A=ABA=AB first and then BA=BBA=B:

A2=A⋅A=(AB)A=A(BA)=AB=AA^2=A\cdot A=(AB)A=A(BA)=AB=A.

So AA is idempotent and A2=AA^2=A.

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