Description: Equality deduction for class abstraction of ordered pairs. (Contributed by Giovanni Mascellani, 10-Apr-2018)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | opabbi | ⊢ ( ∀ 𝑥 ∀ 𝑦 ( 𝜑 ↔ 𝜓 ) → { 〈 𝑥 , 𝑦 〉 ∣ 𝜑 } = { 〈 𝑥 , 𝑦 〉 ∣ 𝜓 } ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | eqopab2b | ⊢ ( { 〈 𝑥 , 𝑦 〉 ∣ 𝜑 } = { 〈 𝑥 , 𝑦 〉 ∣ 𝜓 } ↔ ∀ 𝑥 ∀ 𝑦 ( 𝜑 ↔ 𝜓 ) ) | |
| 2 | 1 | biimpri | ⊢ ( ∀ 𝑥 ∀ 𝑦 ( 𝜑 ↔ 𝜓 ) → { 〈 𝑥 , 𝑦 〉 ∣ 𝜑 } = { 〈 𝑥 , 𝑦 〉 ∣ 𝜓 } ) |