Metamath Proof Explorer


Theorem prtlem12

Description: Lemma for prtex and prter3 . (Contributed by Rodolfo Medina, 13-Oct-2010)

Ref Expression
Assertion prtlem12 ( ∼ = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ 𝐴 ( 𝑥 ∈ 𝑢 ∧ 𝑦 ∈ 𝑢 ) } → Rel ∼ )

Proof

Step Hyp Ref Expression
1 relopabv ⊢ Rel { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ 𝐴 ( 𝑥 ∈ 𝑢 ∧ 𝑦 ∈ 𝑢 ) }
2 releq ⊢ ( ∼ = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ 𝐴 ( 𝑥 ∈ 𝑢 ∧ 𝑦 ∈ 𝑢 ) } → ( Rel ∼ ↔ Rel { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ 𝐴 ( 𝑥 ∈ 𝑢 ∧ 𝑦 ∈ 𝑢 ) } ) )
3 1 2 mpbiri ⊢ ( ∼ = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ 𝐴 ( 𝑥 ∈ 𝑢 ∧ 𝑦 ∈ 𝑢 ) } → Rel ∼ )