Proof of Theorem tgval2
| Step | Hyp | Ref
 | Expression | 
| 1 |   | tgval 12933 | 
. 2
⊢ (𝐵 ∈ 𝑉 → (topGen‘𝐵) = {𝑥 ∣ 𝑥 ⊆ ∪ (𝐵 ∩ 𝒫 𝑥)}) | 
| 2 |   | inss1 3383 | 
. . . . . . . . 9
⊢ (𝐵 ∩ 𝒫 𝑥) ⊆ 𝐵 | 
| 3 | 2 | unissi 3862 | 
. . . . . . . 8
⊢ ∪ (𝐵
∩ 𝒫 𝑥) ⊆
∪ 𝐵 | 
| 4 | 3 | sseli 3179 | 
. . . . . . 7
⊢ (𝑦 ∈ ∪ (𝐵
∩ 𝒫 𝑥) →
𝑦 ∈ ∪ 𝐵) | 
| 5 | 4 | pm4.71ri 392 | 
. . . . . 6
⊢ (𝑦 ∈ ∪ (𝐵
∩ 𝒫 𝑥) ↔
(𝑦 ∈ ∪ 𝐵
∧ 𝑦 ∈ ∪ (𝐵
∩ 𝒫 𝑥))) | 
| 6 | 5 | ralbii 2503 | 
. . . . 5
⊢
(∀𝑦 ∈
𝑥 𝑦 ∈ ∪ (𝐵 ∩ 𝒫 𝑥) ↔ ∀𝑦 ∈ 𝑥 (𝑦 ∈ ∪ 𝐵 ∧ 𝑦 ∈ ∪ (𝐵 ∩ 𝒫 𝑥))) | 
| 7 |   | r19.26 2623 | 
. . . . 5
⊢
(∀𝑦 ∈
𝑥 (𝑦 ∈ ∪ 𝐵 ∧ 𝑦 ∈ ∪ (𝐵 ∩ 𝒫 𝑥)) ↔ (∀𝑦 ∈ 𝑥 𝑦 ∈ ∪ 𝐵 ∧ ∀𝑦 ∈ 𝑥 𝑦 ∈ ∪ (𝐵 ∩ 𝒫 𝑥))) | 
| 8 | 6, 7 | bitri 184 | 
. . . 4
⊢
(∀𝑦 ∈
𝑥 𝑦 ∈ ∪ (𝐵 ∩ 𝒫 𝑥) ↔ (∀𝑦 ∈ 𝑥 𝑦 ∈ ∪ 𝐵 ∧ ∀𝑦 ∈ 𝑥 𝑦 ∈ ∪ (𝐵 ∩ 𝒫 𝑥))) | 
| 9 |   | dfss3 3173 | 
. . . 4
⊢ (𝑥 ⊆ ∪ (𝐵
∩ 𝒫 𝑥) ↔
∀𝑦 ∈ 𝑥 𝑦 ∈ ∪ (𝐵 ∩ 𝒫 𝑥)) | 
| 10 |   | dfss3 3173 | 
. . . . 5
⊢ (𝑥 ⊆ ∪ 𝐵
↔ ∀𝑦 ∈
𝑥 𝑦 ∈ ∪ 𝐵) | 
| 11 |   | elin 3346 | 
. . . . . . . . . . 11
⊢ (𝑧 ∈ (𝐵 ∩ 𝒫 𝑥) ↔ (𝑧 ∈ 𝐵 ∧ 𝑧 ∈ 𝒫 𝑥)) | 
| 12 | 11 | anbi2i 457 | 
. . . . . . . . . 10
⊢ ((𝑦 ∈ 𝑧 ∧ 𝑧 ∈ (𝐵 ∩ 𝒫 𝑥)) ↔ (𝑦 ∈ 𝑧 ∧ (𝑧 ∈ 𝐵 ∧ 𝑧 ∈ 𝒫 𝑥))) | 
| 13 |   | an12 561 | 
. . . . . . . . . 10
⊢ ((𝑦 ∈ 𝑧 ∧ (𝑧 ∈ 𝐵 ∧ 𝑧 ∈ 𝒫 𝑥)) ↔ (𝑧 ∈ 𝐵 ∧ (𝑦 ∈ 𝑧 ∧ 𝑧 ∈ 𝒫 𝑥))) | 
| 14 | 12, 13 | bitri 184 | 
. . . . . . . . 9
⊢ ((𝑦 ∈ 𝑧 ∧ 𝑧 ∈ (𝐵 ∩ 𝒫 𝑥)) ↔ (𝑧 ∈ 𝐵 ∧ (𝑦 ∈ 𝑧 ∧ 𝑧 ∈ 𝒫 𝑥))) | 
| 15 | 14 | exbii 1619 | 
. . . . . . . 8
⊢
(∃𝑧(𝑦 ∈ 𝑧 ∧ 𝑧 ∈ (𝐵 ∩ 𝒫 𝑥)) ↔ ∃𝑧(𝑧 ∈ 𝐵 ∧ (𝑦 ∈ 𝑧 ∧ 𝑧 ∈ 𝒫 𝑥))) | 
| 16 |   | eluni 3842 | 
. . . . . . . 8
⊢ (𝑦 ∈ ∪ (𝐵
∩ 𝒫 𝑥) ↔
∃𝑧(𝑦 ∈ 𝑧 ∧ 𝑧 ∈ (𝐵 ∩ 𝒫 𝑥))) | 
| 17 |   | df-rex 2481 | 
. . . . . . . 8
⊢
(∃𝑧 ∈
𝐵 (𝑦 ∈ 𝑧 ∧ 𝑧 ∈ 𝒫 𝑥) ↔ ∃𝑧(𝑧 ∈ 𝐵 ∧ (𝑦 ∈ 𝑧 ∧ 𝑧 ∈ 𝒫 𝑥))) | 
| 18 | 15, 16, 17 | 3bitr4i 212 | 
. . . . . . 7
⊢ (𝑦 ∈ ∪ (𝐵
∩ 𝒫 𝑥) ↔
∃𝑧 ∈ 𝐵 (𝑦 ∈ 𝑧 ∧ 𝑧 ∈ 𝒫 𝑥)) | 
| 19 |   | velpw 3612 | 
. . . . . . . . 9
⊢ (𝑧 ∈ 𝒫 𝑥 ↔ 𝑧 ⊆ 𝑥) | 
| 20 | 19 | anbi2i 457 | 
. . . . . . . 8
⊢ ((𝑦 ∈ 𝑧 ∧ 𝑧 ∈ 𝒫 𝑥) ↔ (𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥)) | 
| 21 | 20 | rexbii 2504 | 
. . . . . . 7
⊢
(∃𝑧 ∈
𝐵 (𝑦 ∈ 𝑧 ∧ 𝑧 ∈ 𝒫 𝑥) ↔ ∃𝑧 ∈ 𝐵 (𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥)) | 
| 22 | 18, 21 | bitr2i 185 | 
. . . . . 6
⊢
(∃𝑧 ∈
𝐵 (𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥) ↔ 𝑦 ∈ ∪ (𝐵 ∩ 𝒫 𝑥)) | 
| 23 | 22 | ralbii 2503 | 
. . . . 5
⊢
(∀𝑦 ∈
𝑥 ∃𝑧 ∈ 𝐵 (𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥) ↔ ∀𝑦 ∈ 𝑥 𝑦 ∈ ∪ (𝐵 ∩ 𝒫 𝑥)) | 
| 24 | 10, 23 | anbi12i 460 | 
. . . 4
⊢ ((𝑥 ⊆ ∪ 𝐵
∧ ∀𝑦 ∈
𝑥 ∃𝑧 ∈ 𝐵 (𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥)) ↔ (∀𝑦 ∈ 𝑥 𝑦 ∈ ∪ 𝐵 ∧ ∀𝑦 ∈ 𝑥 𝑦 ∈ ∪ (𝐵 ∩ 𝒫 𝑥))) | 
| 25 | 8, 9, 24 | 3bitr4i 212 | 
. . 3
⊢ (𝑥 ⊆ ∪ (𝐵
∩ 𝒫 𝑥) ↔
(𝑥 ⊆ ∪ 𝐵
∧ ∀𝑦 ∈
𝑥 ∃𝑧 ∈ 𝐵 (𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥))) | 
| 26 | 25 | abbii 2312 | 
. 2
⊢ {𝑥 ∣ 𝑥 ⊆ ∪ (𝐵 ∩ 𝒫 𝑥)} = {𝑥 ∣ (𝑥 ⊆ ∪ 𝐵 ∧ ∀𝑦 ∈ 𝑥 ∃𝑧 ∈ 𝐵 (𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥))} | 
| 27 | 1, 26 | eqtrdi 2245 | 
1
⊢ (𝐵 ∈ 𝑉 → (topGen‘𝐵) = {𝑥 ∣ (𝑥 ⊆ ∪ 𝐵 ∧ ∀𝑦 ∈ 𝑥 ∃𝑧 ∈ 𝐵 (𝑦 ∈ 𝑧 ∧ 𝑧 ⊆ 𝑥))}) |