Syntax Definition cun 3119

Description: Extend class notation to include union of two classes (read: "𝐴 union 𝐵").

Hypotheses

Ref	Expression
cA	class 𝐴
cB	class 𝐵

Assertion

Ref	Expression
cun	class (𝐴 ∪ 𝐵)

See definition df-un 3125 for more information.