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Mello
Proper subset VS Subset? Explain the difference please
a set A is a subset of a set B, or equivalently B is a superset of A, if A is contained inside B, thenl elements of A are also elements of B. A and B may coincide. The relationship of one set being a subset of another is called inclusion or containment.
Roughly speaking, a proper subset is one that isn't the set itself.