Union

In set theory, the union of two sets $A, B$ is the set of all elements in $A$ , in $B$ , or both.

Definition
Given two sets $A, B$ , $A\cup B=\{x|x\in A\or x\in B\}$

Example

Suppose $A=\{w,x,y\}$ and $B=\{t,x,z\}$ :

$A\cup B=\{t,w,x,y,z\}$

See also

• Logical disjunction (equivalent in logic)
• Complement (set theory)
• Intersection (set theory)
• Symmetric difference