Let a, b and c be sets. prove a\ (buc) = (a\ b)n (a\c). hint. how to show two sets are equal? problem 1.3. for each function fi, determine whether it is injective but not surjective, or neither injective nor surjective. explain why where ro={r erlz> 0} =[0.00). surjective but not injective, bijective, (1) f. r r with f.(r) 2 for all re r