Discrete Mathematics Definitions

Whitworth Univeristy Dr. Schepens Discrete Mathematics Course

Subset

A ⊆ B ⇔ ∀ x, if x is in A then x is in B.

Proper Subset

A c B ⇔ A ⊆ B and Ǝ x in B such that x is not in A

Set Equality

A = B ⇔ A ⊆ B and B ⊆ A

Union

A u B, all elements are in at least one of A or B

Intersection

A n B, all elements are in both A and B

Difference

B - A, all elements are in B but not in A

Complement

A^c (the negation of A) or U - A, all elements are in U but not in A