Description: Elementhood in a relative intersection. (Contributed by Mario Carneiro, 30-Dec-2016)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | elriin | ⊢ ( 𝐵 ∈ ( 𝐴 ∩ ∩ 𝑥 ∈ 𝑋 𝑆 ) ↔ ( 𝐵 ∈ 𝐴 ∧ ∀ 𝑥 ∈ 𝑋 𝐵 ∈ 𝑆 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elin | ⊢ ( 𝐵 ∈ ( 𝐴 ∩ ∩ 𝑥 ∈ 𝑋 𝑆 ) ↔ ( 𝐵 ∈ 𝐴 ∧ 𝐵 ∈ ∩ 𝑥 ∈ 𝑋 𝑆 ) ) | |
| 2 | eliin | ⊢ ( 𝐵 ∈ 𝐴 → ( 𝐵 ∈ ∩ 𝑥 ∈ 𝑋 𝑆 ↔ ∀ 𝑥 ∈ 𝑋 𝐵 ∈ 𝑆 ) ) | |
| 3 | 2 | pm5.32i | ⊢ ( ( 𝐵 ∈ 𝐴 ∧ 𝐵 ∈ ∩ 𝑥 ∈ 𝑋 𝑆 ) ↔ ( 𝐵 ∈ 𝐴 ∧ ∀ 𝑥 ∈ 𝑋 𝐵 ∈ 𝑆 ) ) |
| 4 | 1 3 | bitri | ⊢ ( 𝐵 ∈ ( 𝐴 ∩ ∩ 𝑥 ∈ 𝑋 𝑆 ) ↔ ( 𝐵 ∈ 𝐴 ∧ ∀ 𝑥 ∈ 𝑋 𝐵 ∈ 𝑆 ) ) |