| Step | Hyp | Ref | Expression | 
						
							| 1 |  | metdscn.f | ⊢ 𝐹  =  ( 𝑥  ∈  𝑋  ↦  inf ( ran  ( 𝑦  ∈  𝑆  ↦  ( 𝑥 𝐷 𝑦 ) ) ,  ℝ* ,   <  ) ) | 
						
							| 2 |  | metdscn.j | ⊢ 𝐽  =  ( MetOpen ‘ 𝐷 ) | 
						
							| 3 |  | simpll1 | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  →  𝐷  ∈  ( ∞Met ‘ 𝑋 ) ) | 
						
							| 4 |  | simprl | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  →  𝑧  ∈  𝐽 ) | 
						
							| 5 |  | simprr | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  →  𝐴  ∈  𝑧 ) | 
						
							| 6 | 2 | mopni2 | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 )  →  ∃ 𝑟  ∈  ℝ+ ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) | 
						
							| 7 | 3 4 5 6 | syl3anc | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  →  ∃ 𝑟  ∈  ℝ+ ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) | 
						
							| 8 |  | simprr | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) | 
						
							| 9 | 8 | ssrind | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ( ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ∩  𝑆 )  ⊆  ( 𝑧  ∩  𝑆 ) ) | 
						
							| 10 |  | rpgt0 | ⊢ ( 𝑟  ∈  ℝ+  →  0  <  𝑟 ) | 
						
							| 11 |  | 0re | ⊢ 0  ∈  ℝ | 
						
							| 12 |  | rpre | ⊢ ( 𝑟  ∈  ℝ+  →  𝑟  ∈  ℝ ) | 
						
							| 13 |  | ltnle | ⊢ ( ( 0  ∈  ℝ  ∧  𝑟  ∈  ℝ )  →  ( 0  <  𝑟  ↔  ¬  𝑟  ≤  0 ) ) | 
						
							| 14 | 11 12 13 | sylancr | ⊢ ( 𝑟  ∈  ℝ+  →  ( 0  <  𝑟  ↔  ¬  𝑟  ≤  0 ) ) | 
						
							| 15 | 10 14 | mpbid | ⊢ ( 𝑟  ∈  ℝ+  →  ¬  𝑟  ≤  0 ) | 
						
							| 16 | 15 | ad2antrl | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ¬  𝑟  ≤  0 ) | 
						
							| 17 |  | simpllr | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ( 𝐹 ‘ 𝐴 )  =  0 ) | 
						
							| 18 | 17 | breq2d | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ( 𝑟  ≤  ( 𝐹 ‘ 𝐴 )  ↔  𝑟  ≤  0 ) ) | 
						
							| 19 | 3 | adantr | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  𝐷  ∈  ( ∞Met ‘ 𝑋 ) ) | 
						
							| 20 |  | simpl2 | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  →  𝑆  ⊆  𝑋 ) | 
						
							| 21 | 20 | ad2antrr | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  𝑆  ⊆  𝑋 ) | 
						
							| 22 |  | simpl3 | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  →  𝐴  ∈  𝑋 ) | 
						
							| 23 | 22 | ad2antrr | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  𝐴  ∈  𝑋 ) | 
						
							| 24 |  | rpxr | ⊢ ( 𝑟  ∈  ℝ+  →  𝑟  ∈  ℝ* ) | 
						
							| 25 | 24 | ad2antrl | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  𝑟  ∈  ℝ* ) | 
						
							| 26 | 1 | metdsge | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝑟  ∈  ℝ* )  →  ( 𝑟  ≤  ( 𝐹 ‘ 𝐴 )  ↔  ( 𝑆  ∩  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 ) )  =  ∅ ) ) | 
						
							| 27 | 19 21 23 25 26 | syl31anc | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ( 𝑟  ≤  ( 𝐹 ‘ 𝐴 )  ↔  ( 𝑆  ∩  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 ) )  =  ∅ ) ) | 
						
							| 28 | 18 27 | bitr3d | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ( 𝑟  ≤  0  ↔  ( 𝑆  ∩  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 ) )  =  ∅ ) ) | 
						
							| 29 |  | incom | ⊢ ( 𝑆  ∩  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 ) )  =  ( ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ∩  𝑆 ) | 
						
							| 30 | 29 | eqeq1i | ⊢ ( ( 𝑆  ∩  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 ) )  =  ∅  ↔  ( ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ∩  𝑆 )  =  ∅ ) | 
						
							| 31 | 28 30 | bitrdi | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ( 𝑟  ≤  0  ↔  ( ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ∩  𝑆 )  =  ∅ ) ) | 
						
							| 32 | 31 | necon3bbid | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ( ¬  𝑟  ≤  0  ↔  ( ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ∩  𝑆 )  ≠  ∅ ) ) | 
						
							| 33 | 16 32 | mpbid | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ( ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ∩  𝑆 )  ≠  ∅ ) | 
						
							| 34 |  | ssn0 | ⊢ ( ( ( ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ∩  𝑆 )  ⊆  ( 𝑧  ∩  𝑆 )  ∧  ( ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ∩  𝑆 )  ≠  ∅ )  →  ( 𝑧  ∩  𝑆 )  ≠  ∅ ) | 
						
							| 35 | 9 33 34 | syl2anc | ⊢ ( ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  ∧  ( 𝑟  ∈  ℝ+  ∧  ( 𝐴 ( ball ‘ 𝐷 ) 𝑟 )  ⊆  𝑧 ) )  →  ( 𝑧  ∩  𝑆 )  ≠  ∅ ) | 
						
							| 36 | 7 35 | rexlimddv | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  ( 𝑧  ∈  𝐽  ∧  𝐴  ∈  𝑧 ) )  →  ( 𝑧  ∩  𝑆 )  ≠  ∅ ) | 
						
							| 37 | 36 | expr | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  ∧  𝑧  ∈  𝐽 )  →  ( 𝐴  ∈  𝑧  →  ( 𝑧  ∩  𝑆 )  ≠  ∅ ) ) | 
						
							| 38 | 37 | ralrimiva | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  →  ∀ 𝑧  ∈  𝐽 ( 𝐴  ∈  𝑧  →  ( 𝑧  ∩  𝑆 )  ≠  ∅ ) ) | 
						
							| 39 | 2 | mopntopon | ⊢ ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  →  𝐽  ∈  ( TopOn ‘ 𝑋 ) ) | 
						
							| 40 | 39 | 3ad2ant1 | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  𝐽  ∈  ( TopOn ‘ 𝑋 ) ) | 
						
							| 41 | 40 | adantr | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  →  𝐽  ∈  ( TopOn ‘ 𝑋 ) ) | 
						
							| 42 |  | topontop | ⊢ ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  →  𝐽  ∈  Top ) | 
						
							| 43 | 41 42 | syl | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  →  𝐽  ∈  Top ) | 
						
							| 44 |  | toponuni | ⊢ ( 𝐽  ∈  ( TopOn ‘ 𝑋 )  →  𝑋  =  ∪  𝐽 ) | 
						
							| 45 | 41 44 | syl | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  →  𝑋  =  ∪  𝐽 ) | 
						
							| 46 | 20 45 | sseqtrd | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  →  𝑆  ⊆  ∪  𝐽 ) | 
						
							| 47 | 22 45 | eleqtrd | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  →  𝐴  ∈  ∪  𝐽 ) | 
						
							| 48 |  | eqid | ⊢ ∪  𝐽  =  ∪  𝐽 | 
						
							| 49 | 48 | elcls | ⊢ ( ( 𝐽  ∈  Top  ∧  𝑆  ⊆  ∪  𝐽  ∧  𝐴  ∈  ∪  𝐽 )  →  ( 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 )  ↔  ∀ 𝑧  ∈  𝐽 ( 𝐴  ∈  𝑧  →  ( 𝑧  ∩  𝑆 )  ≠  ∅ ) ) ) | 
						
							| 50 | 43 46 47 49 | syl3anc | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  →  ( 𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 )  ↔  ∀ 𝑧  ∈  𝐽 ( 𝐴  ∈  𝑧  →  ( 𝑧  ∩  𝑆 )  ≠  ∅ ) ) ) | 
						
							| 51 | 38 50 | mpbird | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  =  0 )  →  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) ) | 
						
							| 52 |  | incom | ⊢ ( ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) )  ∩  𝑆 )  =  ( 𝑆  ∩  ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 53 | 1 | metdsf | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋 )  →  𝐹 : 𝑋 ⟶ ( 0 [,] +∞ ) ) | 
						
							| 54 | 53 | ffvelcdmda | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋 )  ∧  𝐴  ∈  𝑋 )  →  ( 𝐹 ‘ 𝐴 )  ∈  ( 0 [,] +∞ ) ) | 
						
							| 55 | 54 | 3impa | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  ( 𝐹 ‘ 𝐴 )  ∈  ( 0 [,] +∞ ) ) | 
						
							| 56 |  | eliccxr | ⊢ ( ( 𝐹 ‘ 𝐴 )  ∈  ( 0 [,] +∞ )  →  ( 𝐹 ‘ 𝐴 )  ∈  ℝ* ) | 
						
							| 57 | 55 56 | syl | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  ( 𝐹 ‘ 𝐴 )  ∈  ℝ* ) | 
						
							| 58 | 57 | xrleidd | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  ( 𝐹 ‘ 𝐴 )  ≤  ( 𝐹 ‘ 𝐴 ) ) | 
						
							| 59 | 1 | metdsge | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  ( 𝐹 ‘ 𝐴 )  ∈  ℝ* )  →  ( ( 𝐹 ‘ 𝐴 )  ≤  ( 𝐹 ‘ 𝐴 )  ↔  ( 𝑆  ∩  ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) ) )  =  ∅ ) ) | 
						
							| 60 | 57 59 | mpdan | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  ( ( 𝐹 ‘ 𝐴 )  ≤  ( 𝐹 ‘ 𝐴 )  ↔  ( 𝑆  ∩  ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) ) )  =  ∅ ) ) | 
						
							| 61 | 58 60 | mpbid | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  ( 𝑆  ∩  ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) ) )  =  ∅ ) | 
						
							| 62 | 52 61 | eqtrid | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  ( ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) )  ∩  𝑆 )  =  ∅ ) | 
						
							| 63 | 62 | adantr | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  →  ( ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) )  ∩  𝑆 )  =  ∅ ) | 
						
							| 64 | 40 | ad2antrr | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  𝐽  ∈  ( TopOn ‘ 𝑋 ) ) | 
						
							| 65 | 64 42 | syl | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  𝐽  ∈  Top ) | 
						
							| 66 |  | simpll2 | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  𝑆  ⊆  𝑋 ) | 
						
							| 67 | 64 44 | syl | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  𝑋  =  ∪  𝐽 ) | 
						
							| 68 | 66 67 | sseqtrd | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  𝑆  ⊆  ∪  𝐽 ) | 
						
							| 69 |  | simplr | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) ) | 
						
							| 70 |  | simpll1 | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  𝐷  ∈  ( ∞Met ‘ 𝑋 ) ) | 
						
							| 71 |  | simpll3 | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  𝐴  ∈  𝑋 ) | 
						
							| 72 | 57 | ad2antrr | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  ( 𝐹 ‘ 𝐴 )  ∈  ℝ* ) | 
						
							| 73 | 2 | blopn | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝐴  ∈  𝑋  ∧  ( 𝐹 ‘ 𝐴 )  ∈  ℝ* )  →  ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) )  ∈  𝐽 ) | 
						
							| 74 | 70 71 72 73 | syl3anc | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) )  ∈  𝐽 ) | 
						
							| 75 |  | simpr | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  0  <  ( 𝐹 ‘ 𝐴 ) ) | 
						
							| 76 |  | xblcntr | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝐴  ∈  𝑋  ∧  ( ( 𝐹 ‘ 𝐴 )  ∈  ℝ*  ∧  0  <  ( 𝐹 ‘ 𝐴 ) ) )  →  𝐴  ∈  ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 77 | 70 71 72 75 76 | syl112anc | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  𝐴  ∈  ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 78 | 48 | clsndisj | ⊢ ( ( ( 𝐽  ∈  Top  ∧  𝑆  ⊆  ∪  𝐽  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  ( ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) )  ∈  𝐽  ∧  𝐴  ∈  ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) ) ) )  →  ( ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) )  ∩  𝑆 )  ≠  ∅ ) | 
						
							| 79 | 65 68 69 74 77 78 | syl32anc | ⊢ ( ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  ∧  0  <  ( 𝐹 ‘ 𝐴 ) )  →  ( ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) )  ∩  𝑆 )  ≠  ∅ ) | 
						
							| 80 | 79 | ex | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  →  ( 0  <  ( 𝐹 ‘ 𝐴 )  →  ( ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) )  ∩  𝑆 )  ≠  ∅ ) ) | 
						
							| 81 | 80 | necon2bd | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  →  ( ( ( 𝐴 ( ball ‘ 𝐷 ) ( 𝐹 ‘ 𝐴 ) )  ∩  𝑆 )  =  ∅  →  ¬  0  <  ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 82 | 63 81 | mpd | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  →  ¬  0  <  ( 𝐹 ‘ 𝐴 ) ) | 
						
							| 83 |  | elxrge0 | ⊢ ( ( 𝐹 ‘ 𝐴 )  ∈  ( 0 [,] +∞ )  ↔  ( ( 𝐹 ‘ 𝐴 )  ∈  ℝ*  ∧  0  ≤  ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 84 | 83 | simprbi | ⊢ ( ( 𝐹 ‘ 𝐴 )  ∈  ( 0 [,] +∞ )  →  0  ≤  ( 𝐹 ‘ 𝐴 ) ) | 
						
							| 85 | 55 84 | syl | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  0  ≤  ( 𝐹 ‘ 𝐴 ) ) | 
						
							| 86 |  | 0xr | ⊢ 0  ∈  ℝ* | 
						
							| 87 |  | xrleloe | ⊢ ( ( 0  ∈  ℝ*  ∧  ( 𝐹 ‘ 𝐴 )  ∈  ℝ* )  →  ( 0  ≤  ( 𝐹 ‘ 𝐴 )  ↔  ( 0  <  ( 𝐹 ‘ 𝐴 )  ∨  0  =  ( 𝐹 ‘ 𝐴 ) ) ) ) | 
						
							| 88 | 86 57 87 | sylancr | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  ( 0  ≤  ( 𝐹 ‘ 𝐴 )  ↔  ( 0  <  ( 𝐹 ‘ 𝐴 )  ∨  0  =  ( 𝐹 ‘ 𝐴 ) ) ) ) | 
						
							| 89 | 85 88 | mpbid | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  ( 0  <  ( 𝐹 ‘ 𝐴 )  ∨  0  =  ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 90 | 89 | adantr | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  →  ( 0  <  ( 𝐹 ‘ 𝐴 )  ∨  0  =  ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 91 | 90 | ord | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  →  ( ¬  0  <  ( 𝐹 ‘ 𝐴 )  →  0  =  ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 92 | 82 91 | mpd | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  →  0  =  ( 𝐹 ‘ 𝐴 ) ) | 
						
							| 93 | 92 | eqcomd | ⊢ ( ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  ∧  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) )  →  ( 𝐹 ‘ 𝐴 )  =  0 ) | 
						
							| 94 | 51 93 | impbida | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝑋 )  ∧  𝑆  ⊆  𝑋  ∧  𝐴  ∈  𝑋 )  →  ( ( 𝐹 ‘ 𝐴 )  =  0  ↔  𝐴  ∈  ( ( cls ‘ 𝐽 ) ‘ 𝑆 ) ) ) |