Proof of Theorem supnfcls
Step | Hyp | Ref
| Expression |
1 | | disjdif 4411 |
. 2
⊢ (𝑈 ∩ (𝑋 ∖ 𝑈)) = ∅ |
2 | | simpr 485 |
. . . . 5
⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) ∧ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) → 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) |
3 | | simpl2 1191 |
. . . . 5
⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) ∧ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) → 𝑈 ∈ 𝐽) |
4 | | simpl3 1192 |
. . . . 5
⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) ∧ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) → 𝐴 ∈ 𝑈) |
5 | | sseq2 3952 |
. . . . . 6
⊢ (𝑥 = (𝑋 ∖ 𝑈) → ((𝑋 ∖ 𝑈) ⊆ 𝑥 ↔ (𝑋 ∖ 𝑈) ⊆ (𝑋 ∖ 𝑈))) |
6 | | difss 4071 |
. . . . . . 7
⊢ (𝑋 ∖ 𝑈) ⊆ 𝑋 |
7 | | simpl1 1190 |
. . . . . . . 8
⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) ∧ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) → 𝐽 ∈ (TopOn‘𝑋)) |
8 | | toponmax 22073 |
. . . . . . . 8
⊢ (𝐽 ∈ (TopOn‘𝑋) → 𝑋 ∈ 𝐽) |
9 | | elpw2g 5272 |
. . . . . . . 8
⊢ (𝑋 ∈ 𝐽 → ((𝑋 ∖ 𝑈) ∈ 𝒫 𝑋 ↔ (𝑋 ∖ 𝑈) ⊆ 𝑋)) |
10 | 7, 8, 9 | 3syl 18 |
. . . . . . 7
⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) ∧ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) → ((𝑋 ∖ 𝑈) ∈ 𝒫 𝑋 ↔ (𝑋 ∖ 𝑈) ⊆ 𝑋)) |
11 | 6, 10 | mpbiri 257 |
. . . . . 6
⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) ∧ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) → (𝑋 ∖ 𝑈) ∈ 𝒫 𝑋) |
12 | | ssidd 3949 |
. . . . . 6
⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) ∧ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) → (𝑋 ∖ 𝑈) ⊆ (𝑋 ∖ 𝑈)) |
13 | 5, 11, 12 | elrabd 3628 |
. . . . 5
⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) ∧ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) → (𝑋 ∖ 𝑈) ∈ {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥}) |
14 | | fclsopni 23164 |
. . . . 5
⊢ ((𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥}) ∧ (𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈 ∧ (𝑋 ∖ 𝑈) ∈ {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) → (𝑈 ∩ (𝑋 ∖ 𝑈)) ≠ ∅) |
15 | 2, 3, 4, 13, 14 | syl13anc 1371 |
. . . 4
⊢ (((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) ∧ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) → (𝑈 ∩ (𝑋 ∖ 𝑈)) ≠ ∅) |
16 | 15 | ex 413 |
. . 3
⊢ ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) → (𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥}) → (𝑈 ∩ (𝑋 ∖ 𝑈)) ≠ ∅)) |
17 | 16 | necon2bd 2961 |
. 2
⊢ ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) → ((𝑈 ∩ (𝑋 ∖ 𝑈)) = ∅ → ¬ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥}))) |
18 | 1, 17 | mpi 20 |
1
⊢ ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝑈 ∈ 𝐽 ∧ 𝐴 ∈ 𝑈) → ¬ 𝐴 ∈ (𝐽 fClus {𝑥 ∈ 𝒫 𝑋 ∣ (𝑋 ∖ 𝑈) ⊆ 𝑥})) |