Proof of Theorem blssexps
| Step | Hyp | Ref
 | Expression | 
| 1 |   | blssps 14663 | 
. . . . . . 7
⊢ ((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑥 ∈ ran (ball‘𝐷) ∧ 𝑃 ∈ 𝑥) → ∃𝑟 ∈ ℝ+ (𝑃(ball‘𝐷)𝑟) ⊆ 𝑥) | 
| 2 |   | sstr 3191 | 
. . . . . . . . 9
⊢ (((𝑃(ball‘𝐷)𝑟) ⊆ 𝑥 ∧ 𝑥 ⊆ 𝐴) → (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴) | 
| 3 | 2 | expcom 116 | 
. . . . . . . 8
⊢ (𝑥 ⊆ 𝐴 → ((𝑃(ball‘𝐷)𝑟) ⊆ 𝑥 → (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) | 
| 4 | 3 | reximdv 2598 | 
. . . . . . 7
⊢ (𝑥 ⊆ 𝐴 → (∃𝑟 ∈ ℝ+ (𝑃(ball‘𝐷)𝑟) ⊆ 𝑥 → ∃𝑟 ∈ ℝ+ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) | 
| 5 | 1, 4 | syl5com 29 | 
. . . . . 6
⊢ ((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑥 ∈ ran (ball‘𝐷) ∧ 𝑃 ∈ 𝑥) → (𝑥 ⊆ 𝐴 → ∃𝑟 ∈ ℝ+ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) | 
| 6 | 5 | 3expa 1205 | 
. . . . 5
⊢ (((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑥 ∈ ran (ball‘𝐷)) ∧ 𝑃 ∈ 𝑥) → (𝑥 ⊆ 𝐴 → ∃𝑟 ∈ ℝ+ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) | 
| 7 | 6 | expimpd 363 | 
. . . 4
⊢ ((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑥 ∈ ran (ball‘𝐷)) → ((𝑃 ∈ 𝑥 ∧ 𝑥 ⊆ 𝐴) → ∃𝑟 ∈ ℝ+ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) | 
| 8 | 7 | adantlr 477 | 
. . 3
⊢ (((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) ∧ 𝑥 ∈ ran (ball‘𝐷)) → ((𝑃 ∈ 𝑥 ∧ 𝑥 ⊆ 𝐴) → ∃𝑟 ∈ ℝ+ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) | 
| 9 | 8 | rexlimdva 2614 | 
. 2
⊢ ((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) → (∃𝑥 ∈ ran (ball‘𝐷)(𝑃 ∈ 𝑥 ∧ 𝑥 ⊆ 𝐴) → ∃𝑟 ∈ ℝ+ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) | 
| 10 |   | simpll 527 | 
. . . . 5
⊢ (((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) ∧ (𝑟 ∈ ℝ+ ∧ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) → 𝐷 ∈ (PsMet‘𝑋)) | 
| 11 |   | simplr 528 | 
. . . . 5
⊢ (((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) ∧ (𝑟 ∈ ℝ+ ∧ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) → 𝑃 ∈ 𝑋) | 
| 12 |   | rpxr 9736 | 
. . . . . 6
⊢ (𝑟 ∈ ℝ+
→ 𝑟 ∈
ℝ*) | 
| 13 | 12 | ad2antrl 490 | 
. . . . 5
⊢ (((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) ∧ (𝑟 ∈ ℝ+ ∧ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) → 𝑟 ∈ ℝ*) | 
| 14 |   | blelrnps 14655 | 
. . . . 5
⊢ ((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋 ∧ 𝑟 ∈ ℝ*) → (𝑃(ball‘𝐷)𝑟) ∈ ran (ball‘𝐷)) | 
| 15 | 10, 11, 13, 14 | syl3anc 1249 | 
. . . 4
⊢ (((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) ∧ (𝑟 ∈ ℝ+ ∧ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) → (𝑃(ball‘𝐷)𝑟) ∈ ran (ball‘𝐷)) | 
| 16 |   | simprl 529 | 
. . . . 5
⊢ (((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) ∧ (𝑟 ∈ ℝ+ ∧ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) → 𝑟 ∈ ℝ+) | 
| 17 |   | blcntrps 14651 | 
. . . . 5
⊢ ((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋 ∧ 𝑟 ∈ ℝ+) → 𝑃 ∈ (𝑃(ball‘𝐷)𝑟)) | 
| 18 | 10, 11, 16, 17 | syl3anc 1249 | 
. . . 4
⊢ (((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) ∧ (𝑟 ∈ ℝ+ ∧ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) → 𝑃 ∈ (𝑃(ball‘𝐷)𝑟)) | 
| 19 |   | simprr 531 | 
. . . 4
⊢ (((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) ∧ (𝑟 ∈ ℝ+ ∧ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) → (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴) | 
| 20 |   | eleq2 2260 | 
. . . . . 6
⊢ (𝑥 = (𝑃(ball‘𝐷)𝑟) → (𝑃 ∈ 𝑥 ↔ 𝑃 ∈ (𝑃(ball‘𝐷)𝑟))) | 
| 21 |   | sseq1 3206 | 
. . . . . 6
⊢ (𝑥 = (𝑃(ball‘𝐷)𝑟) → (𝑥 ⊆ 𝐴 ↔ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) | 
| 22 | 20, 21 | anbi12d 473 | 
. . . . 5
⊢ (𝑥 = (𝑃(ball‘𝐷)𝑟) → ((𝑃 ∈ 𝑥 ∧ 𝑥 ⊆ 𝐴) ↔ (𝑃 ∈ (𝑃(ball‘𝐷)𝑟) ∧ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴))) | 
| 23 | 22 | rspcev 2868 | 
. . . 4
⊢ (((𝑃(ball‘𝐷)𝑟) ∈ ran (ball‘𝐷) ∧ (𝑃 ∈ (𝑃(ball‘𝐷)𝑟) ∧ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) → ∃𝑥 ∈ ran (ball‘𝐷)(𝑃 ∈ 𝑥 ∧ 𝑥 ⊆ 𝐴)) | 
| 24 | 15, 18, 19, 23 | syl12anc 1247 | 
. . 3
⊢ (((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) ∧ (𝑟 ∈ ℝ+ ∧ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) → ∃𝑥 ∈ ran (ball‘𝐷)(𝑃 ∈ 𝑥 ∧ 𝑥 ⊆ 𝐴)) | 
| 25 | 24 | rexlimdvaa 2615 | 
. 2
⊢ ((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) → (∃𝑟 ∈ ℝ+ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴 → ∃𝑥 ∈ ran (ball‘𝐷)(𝑃 ∈ 𝑥 ∧ 𝑥 ⊆ 𝐴))) | 
| 26 | 9, 25 | impbid 129 | 
1
⊢ ((𝐷 ∈ (PsMet‘𝑋) ∧ 𝑃 ∈ 𝑋) → (∃𝑥 ∈ ran (ball‘𝐷)(𝑃 ∈ 𝑥 ∧ 𝑥 ⊆ 𝐴) ↔ ∃𝑟 ∈ ℝ+ (𝑃(ball‘𝐷)𝑟) ⊆ 𝐴)) |