Metamath Proof Explorer


Theorem ssrab2f

Description: Subclass relation for a restricted class. (Contributed by Glauco Siliprandi, 26-Jun-2021)

Ref Expression
Hypothesis ssrab2f.1 ⊢ Ⅎ _ x A
Assertion ssrab2f ⊢ x ∈ A | φ ⊆ A

Proof

Step Hyp Ref Expression
1 ssrab2f.1 ⊢ Ⅎ _ x A
2 nfrab1 ⊢ Ⅎ _ x x ∈ A | φ
3 2 1 dfss3f ⊢ x ∈ A | φ ⊆ A ↔ ∀ x ∈ x ∈ A | φ x ∈ A
4 rabidim1 ⊢ x ∈ x ∈ A | φ → x ∈ A
5 3 4 mprgbir ⊢ x ∈ A | φ ⊆ A