Metamath Proof Explorer


Theorem bnj918

Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

Ref Expression
Hypothesis bnj918.1 ⊢ G = f ∪ n C
Assertion bnj918 ⊢ G ∈ V

Proof

Step Hyp Ref Expression
1 bnj918.1 ⊢ G = f ∪ n C
2 vex ⊢ f ∈ V
3 snex ⊢ n C ∈ V
4 2 3 unex ⊢ f ∪ n C ∈ V
5 1 4 eqeltri ⊢ G ∈ V