Metamath Proof Explorer


Theorem elrint2

Description: Membership in a restricted intersection. (Contributed by Stefan O'Rear, 3-Apr-2015)

Ref Expression
Assertion elrint2 ( 𝑋 ∈ 𝐴 → ( 𝑋 ∈ ( 𝐴 ∩ ∩ 𝐵 ) ↔ ∀ 𝑦 ∈ 𝐵 𝑋 ∈ 𝑦 ) )

Proof

Step Hyp Ref Expression
1 elrint ⊢ ( 𝑋 ∈ ( 𝐴 ∩ ∩ 𝐵 ) ↔ ( 𝑋 ∈ 𝐴 ∧ ∀ 𝑦 ∈ 𝐵 𝑋 ∈ 𝑦 ) )
2 1 baib ⊢ ( 𝑋 ∈ 𝐴 → ( 𝑋 ∈ ( 𝐴 ∩ ∩ 𝐵 ) ↔ ∀ 𝑦 ∈ 𝐵 𝑋 ∈ 𝑦 ) )