For any two sets A and B, prove the following:

A – B = A Δ (A B)

= A Δ (A B) [ E Δ F =(E–F) (F–E) ]


= (A–( A B)) (A B –A) [ E – F = E F’]


= (A (A B)’) (ABA’)


= (A (A’B’)) (AA’B)


= ϕ (A B’) ϕ


= A B’ [A B’ = A–B]


= A–B


=LHS


LHS=RHS Proved.


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