Metamath Proof Explorer


Theorem eliinid

Description: Membership in an indexed intersection implies membership in any intersected set. (Contributed by Glauco Siliprandi, 26-Jun-2021)

Ref Expression
Assertion eliinid ⊢ A ∈ ⋂ x ∈ B C ∧ x ∈ B → A ∈ C

Proof

Step Hyp Ref Expression
1 simpl ⊢ A ∈ ⋂ x ∈ B C ∧ x ∈ B → A ∈ ⋂ x ∈ B C
2 eliin ⊢ A ∈ ⋂ x ∈ B C → A ∈ ⋂ x ∈ B C ↔ ∀ x ∈ B A ∈ C
3 2 adantr ⊢ A ∈ ⋂ x ∈ B C ∧ x ∈ B → A ∈ ⋂ x ∈ B C ↔ ∀ x ∈ B A ∈ C
4 1 3 mpbid ⊢ A ∈ ⋂ x ∈ B C ∧ x ∈ B → ∀ x ∈ B A ∈ C
5 rspa ⊢ ∀ x ∈ B A ∈ C ∧ x ∈ B → A ∈ C
6 4 5 sylancom ⊢ A ∈ ⋂ x ∈ B C ∧ x ∈ B → A ∈ C