Step |
Hyp |
Ref |
Expression |
1 |
|
isfne.1 |
⊢ 𝑋 = ∪ 𝐴 |
2 |
|
isfne.2 |
⊢ 𝑌 = ∪ 𝐵 |
3 |
1 2
|
isfne4 |
⊢ ( 𝐴 Fne 𝐵 ↔ ( 𝑋 = 𝑌 ∧ 𝐴 ⊆ ( topGen ‘ 𝐵 ) ) ) |
4 |
|
dfss3 |
⊢ ( 𝐴 ⊆ ( topGen ‘ 𝐵 ) ↔ ∀ 𝑥 ∈ 𝐴 𝑥 ∈ ( topGen ‘ 𝐵 ) ) |
5 |
|
eltg2b |
⊢ ( 𝐵 ∈ 𝐶 → ( 𝑥 ∈ ( topGen ‘ 𝐵 ) ↔ ∀ 𝑦 ∈ 𝑥 ∃ 𝑧 ∈ 𝐵 ( 𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥 ) ) ) |
6 |
5
|
ralbidv |
⊢ ( 𝐵 ∈ 𝐶 → ( ∀ 𝑥 ∈ 𝐴 𝑥 ∈ ( topGen ‘ 𝐵 ) ↔ ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝑥 ∃ 𝑧 ∈ 𝐵 ( 𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥 ) ) ) |
7 |
4 6
|
syl5bb |
⊢ ( 𝐵 ∈ 𝐶 → ( 𝐴 ⊆ ( topGen ‘ 𝐵 ) ↔ ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝑥 ∃ 𝑧 ∈ 𝐵 ( 𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥 ) ) ) |
8 |
7
|
anbi2d |
⊢ ( 𝐵 ∈ 𝐶 → ( ( 𝑋 = 𝑌 ∧ 𝐴 ⊆ ( topGen ‘ 𝐵 ) ) ↔ ( 𝑋 = 𝑌 ∧ ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝑥 ∃ 𝑧 ∈ 𝐵 ( 𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥 ) ) ) ) |
9 |
3 8
|
syl5bb |
⊢ ( 𝐵 ∈ 𝐶 → ( 𝐴 Fne 𝐵 ↔ ( 𝑋 = 𝑌 ∧ ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝑥 ∃ 𝑧 ∈ 𝐵 ( 𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥 ) ) ) ) |