This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Restricted class abstraction in a subclass relationship. (Contributed by Glauco Siliprandi, 26-Jun-2021)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | rabssf.1 | ⊢ Ⅎ 𝑥 𝐵 | |
| Assertion | rabssf | ⊢ ( { 𝑥 ∈ 𝐴 ∣ 𝜑 } ⊆ 𝐵 ↔ ∀ 𝑥 ∈ 𝐴 ( 𝜑 → 𝑥 ∈ 𝐵 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | rabssf.1 | ⊢ Ⅎ 𝑥 𝐵 | |
| 2 | df-rab | ⊢ { 𝑥 ∈ 𝐴 ∣ 𝜑 } = { 𝑥 ∣ ( 𝑥 ∈ 𝐴 ∧ 𝜑 ) } | |
| 3 | 2 | sseq1i | ⊢ ( { 𝑥 ∈ 𝐴 ∣ 𝜑 } ⊆ 𝐵 ↔ { 𝑥 ∣ ( 𝑥 ∈ 𝐴 ∧ 𝜑 ) } ⊆ 𝐵 ) |
| 4 | 1 | abssf | ⊢ ( { 𝑥 ∣ ( 𝑥 ∈ 𝐴 ∧ 𝜑 ) } ⊆ 𝐵 ↔ ∀ 𝑥 ( ( 𝑥 ∈ 𝐴 ∧ 𝜑 ) → 𝑥 ∈ 𝐵 ) ) |
| 5 | impexp | ⊢ ( ( ( 𝑥 ∈ 𝐴 ∧ 𝜑 ) → 𝑥 ∈ 𝐵 ) ↔ ( 𝑥 ∈ 𝐴 → ( 𝜑 → 𝑥 ∈ 𝐵 ) ) ) | |
| 6 | 5 | albii | ⊢ ( ∀ 𝑥 ( ( 𝑥 ∈ 𝐴 ∧ 𝜑 ) → 𝑥 ∈ 𝐵 ) ↔ ∀ 𝑥 ( 𝑥 ∈ 𝐴 → ( 𝜑 → 𝑥 ∈ 𝐵 ) ) ) |
| 7 | df-ral | ⊢ ( ∀ 𝑥 ∈ 𝐴 ( 𝜑 → 𝑥 ∈ 𝐵 ) ↔ ∀ 𝑥 ( 𝑥 ∈ 𝐴 → ( 𝜑 → 𝑥 ∈ 𝐵 ) ) ) | |
| 8 | 6 7 | bitr4i | ⊢ ( ∀ 𝑥 ( ( 𝑥 ∈ 𝐴 ∧ 𝜑 ) → 𝑥 ∈ 𝐵 ) ↔ ∀ 𝑥 ∈ 𝐴 ( 𝜑 → 𝑥 ∈ 𝐵 ) ) |
| 9 | 3 4 8 | 3bitri | ⊢ ( { 𝑥 ∈ 𝐴 ∣ 𝜑 } ⊆ 𝐵 ↔ ∀ 𝑥 ∈ 𝐴 ( 𝜑 → 𝑥 ∈ 𝐵 ) ) |