Description: Condition for an operation to be a set. (Contributed by Thierry Arnoux, 25-Jun-2019)
Ref | Expression | ||
---|---|---|---|
Hypotheses | opabex2.1 | ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 ) | |
opabex2.2 | ⊢ ( 𝜑 → 𝐵 ∈ 𝑊 ) | ||
opabex2.3 | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝑥 ∈ 𝐴 ) | ||
opabex2.4 | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝑦 ∈ 𝐵 ) | ||
Assertion | opabex2 | ⊢ ( 𝜑 → { 〈 𝑥 , 𝑦 〉 ∣ 𝜓 } ∈ V ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | opabex2.1 | ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 ) | |
2 | opabex2.2 | ⊢ ( 𝜑 → 𝐵 ∈ 𝑊 ) | |
3 | opabex2.3 | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝑥 ∈ 𝐴 ) | |
4 | opabex2.4 | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝑦 ∈ 𝐵 ) | |
5 | 1 2 | xpexd | ⊢ ( 𝜑 → ( 𝐴 × 𝐵 ) ∈ V ) |
6 | 3 4 | opabssxpd | ⊢ ( 𝜑 → { 〈 𝑥 , 𝑦 〉 ∣ 𝜓 } ⊆ ( 𝐴 × 𝐵 ) ) |
7 | 5 6 | ssexd | ⊢ ( 𝜑 → { 〈 𝑥 , 𝑦 〉 ∣ 𝜓 } ∈ V ) |