Homework Statement
Prove the following for a given universe U
A⊆B if and only if A∩(B compliment) = ∅
Homework EquationsThe Attempt at a Solution
Assume A,B, (B compliment) are not ∅
if A∩(B compliment) = ∅, x∈A ∨ x∈ (B compliment), but not both
If x∈A ∧ x∉(B compliment), then x∈B , because...