- #1
eyehategod
- 82
- 0
If A and B are idempotent(A=A^2) and AB=BA, prove that AB is idempotent.
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?
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?