Description: Equality of generalized class abstractions. Deduction form. (Contributed by BJ, 4-Oct-2024)
Ref | Expression | ||
---|---|---|---|
Hypotheses | bj-gabeqd.nf | ⊢ ( 𝜑 → ∀ 𝑥 𝜑 ) | |
bj-gabeqd.c | ⊢ ( 𝜑 → 𝐴 = 𝐵 ) | ||
bj-gabeqd.f | ⊢ ( 𝜑 → ( 𝜓 ↔ 𝜒 ) ) | ||
Assertion | bj-gabeqd | ⊢ ( 𝜑 → { 𝐴 ∣ 𝑥 ∣ 𝜓 } = { 𝐵 ∣ 𝑥 ∣ 𝜒 } ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | bj-gabeqd.nf | ⊢ ( 𝜑 → ∀ 𝑥 𝜑 ) | |
2 | bj-gabeqd.c | ⊢ ( 𝜑 → 𝐴 = 𝐵 ) | |
3 | bj-gabeqd.f | ⊢ ( 𝜑 → ( 𝜓 ↔ 𝜒 ) ) | |
4 | 3 | biimpd | ⊢ ( 𝜑 → ( 𝜓 → 𝜒 ) ) |
5 | 1 2 4 | bj-gabssd | ⊢ ( 𝜑 → { 𝐴 ∣ 𝑥 ∣ 𝜓 } ⊆ { 𝐵 ∣ 𝑥 ∣ 𝜒 } ) |
6 | 2 | eqcomd | ⊢ ( 𝜑 → 𝐵 = 𝐴 ) |
7 | 3 | biimprd | ⊢ ( 𝜑 → ( 𝜒 → 𝜓 ) ) |
8 | 1 6 7 | bj-gabssd | ⊢ ( 𝜑 → { 𝐵 ∣ 𝑥 ∣ 𝜒 } ⊆ { 𝐴 ∣ 𝑥 ∣ 𝜓 } ) |
9 | 5 8 | eqssd | ⊢ ( 𝜑 → { 𝐴 ∣ 𝑥 ∣ 𝜓 } = { 𝐵 ∣ 𝑥 ∣ 𝜒 } ) |