Theorem uniexd

Description: Deduction version of the ZF Axiom of Union in class notation. (Contributed by Glauco Siliprandi, 26-Jun-2021)

	Ref	Expression
Hypothesis	uniexd.1	|- ( ph -> A e. V )
Assertion	uniexd	|- ( ph -> U. A e. _V )

Proof

Step	Hyp	Ref	Expression
1		uniexd.1	|- ( ph -> A e. V )
2		uniexg	|- ( A e. V -> U. A e. _V )
3	1 2	syl	|- ( ph -> U. A e. _V )