Metamath Proof Explorer


Theorem inex1g

Description: Closed-form, generalized Separation Scheme. (Contributed by NM, 7-Apr-1995)

Ref Expression
Assertion inex1g ( 𝐴𝑉 → ( 𝐴𝐵 ) ∈ V )

Proof

Step Hyp Ref Expression
1 ineq1 ( 𝑥 = 𝐴 → ( 𝑥𝐵 ) = ( 𝐴𝐵 ) )
2 1 eleq1d ( 𝑥 = 𝐴 → ( ( 𝑥𝐵 ) ∈ V ↔ ( 𝐴𝐵 ) ∈ V ) )
3 vex 𝑥 ∈ V
4 3 inex1 ( 𝑥𝐵 ) ∈ V
5 2 4 vtoclg ( 𝐴𝑉 → ( 𝐴𝐵 ) ∈ V )