| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ftc1cn.g | ⊢ 𝐺  =  ( 𝑥  ∈  ( 𝐴 [,] 𝐵 )  ↦  ∫ ( 𝐴 (,) 𝑥 ) ( 𝐹 ‘ 𝑡 )  d 𝑡 ) | 
						
							| 2 |  | ftc1cn.a | ⊢ ( 𝜑  →  𝐴  ∈  ℝ ) | 
						
							| 3 |  | ftc1cn.b | ⊢ ( 𝜑  →  𝐵  ∈  ℝ ) | 
						
							| 4 |  | ftc1cn.le | ⊢ ( 𝜑  →  𝐴  ≤  𝐵 ) | 
						
							| 5 |  | ftc1cn.f | ⊢ ( 𝜑  →  𝐹  ∈  ( ( 𝐴 (,) 𝐵 ) –cn→ ℂ ) ) | 
						
							| 6 |  | ftc1cn.i | ⊢ ( 𝜑  →  𝐹  ∈  𝐿1 ) | 
						
							| 7 |  | dvf | ⊢ ( ℝ  D  𝐺 ) : dom  ( ℝ  D  𝐺 ) ⟶ ℂ | 
						
							| 8 | 7 | a1i | ⊢ ( 𝜑  →  ( ℝ  D  𝐺 ) : dom  ( ℝ  D  𝐺 ) ⟶ ℂ ) | 
						
							| 9 | 8 | ffund | ⊢ ( 𝜑  →  Fun  ( ℝ  D  𝐺 ) ) | 
						
							| 10 |  | ax-resscn | ⊢ ℝ  ⊆  ℂ | 
						
							| 11 | 10 | a1i | ⊢ ( 𝜑  →  ℝ  ⊆  ℂ ) | 
						
							| 12 |  | ssidd | ⊢ ( 𝜑  →  ( 𝐴 (,) 𝐵 )  ⊆  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 13 |  | ioossre | ⊢ ( 𝐴 (,) 𝐵 )  ⊆  ℝ | 
						
							| 14 | 13 | a1i | ⊢ ( 𝜑  →  ( 𝐴 (,) 𝐵 )  ⊆  ℝ ) | 
						
							| 15 |  | cncff | ⊢ ( 𝐹  ∈  ( ( 𝐴 (,) 𝐵 ) –cn→ ℂ )  →  𝐹 : ( 𝐴 (,) 𝐵 ) ⟶ ℂ ) | 
						
							| 16 | 5 15 | syl | ⊢ ( 𝜑  →  𝐹 : ( 𝐴 (,) 𝐵 ) ⟶ ℂ ) | 
						
							| 17 | 1 2 3 4 12 14 6 16 | ftc1lem2 | ⊢ ( 𝜑  →  𝐺 : ( 𝐴 [,] 𝐵 ) ⟶ ℂ ) | 
						
							| 18 |  | iccssre | ⊢ ( ( 𝐴  ∈  ℝ  ∧  𝐵  ∈  ℝ )  →  ( 𝐴 [,] 𝐵 )  ⊆  ℝ ) | 
						
							| 19 | 2 3 18 | syl2anc | ⊢ ( 𝜑  →  ( 𝐴 [,] 𝐵 )  ⊆  ℝ ) | 
						
							| 20 |  | tgioo4 | ⊢ ( topGen ‘ ran  (,) )  =  ( ( TopOpen ‘ ℂfld )  ↾t  ℝ ) | 
						
							| 21 |  | eqid | ⊢ ( TopOpen ‘ ℂfld )  =  ( TopOpen ‘ ℂfld ) | 
						
							| 22 | 11 17 19 20 21 | dvbssntr | ⊢ ( 𝜑  →  dom  ( ℝ  D  𝐺 )  ⊆  ( ( int ‘ ( topGen ‘ ran  (,) ) ) ‘ ( 𝐴 [,] 𝐵 ) ) ) | 
						
							| 23 |  | iccntr | ⊢ ( ( 𝐴  ∈  ℝ  ∧  𝐵  ∈  ℝ )  →  ( ( int ‘ ( topGen ‘ ran  (,) ) ) ‘ ( 𝐴 [,] 𝐵 ) )  =  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 24 | 2 3 23 | syl2anc | ⊢ ( 𝜑  →  ( ( int ‘ ( topGen ‘ ran  (,) ) ) ‘ ( 𝐴 [,] 𝐵 ) )  =  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 25 | 22 24 | sseqtrd | ⊢ ( 𝜑  →  dom  ( ℝ  D  𝐺 )  ⊆  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 26 | 2 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  𝐴  ∈  ℝ ) | 
						
							| 27 | 3 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  𝐵  ∈  ℝ ) | 
						
							| 28 | 4 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  𝐴  ≤  𝐵 ) | 
						
							| 29 |  | ssidd | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  ( 𝐴 (,) 𝐵 )  ⊆  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 30 | 13 | a1i | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  ( 𝐴 (,) 𝐵 )  ⊆  ℝ ) | 
						
							| 31 | 6 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  𝐹  ∈  𝐿1 ) | 
						
							| 32 |  | simpr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  𝑦  ∈  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 33 | 13 10 | sstri | ⊢ ( 𝐴 (,) 𝐵 )  ⊆  ℂ | 
						
							| 34 |  | ssid | ⊢ ℂ  ⊆  ℂ | 
						
							| 35 |  | eqid | ⊢ ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  =  ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 36 | 21 | cnfldtopon | ⊢ ( TopOpen ‘ ℂfld )  ∈  ( TopOn ‘ ℂ ) | 
						
							| 37 | 36 | toponrestid | ⊢ ( TopOpen ‘ ℂfld )  =  ( ( TopOpen ‘ ℂfld )  ↾t  ℂ ) | 
						
							| 38 | 21 35 37 | cncfcn | ⊢ ( ( ( 𝐴 (,) 𝐵 )  ⊆  ℂ  ∧  ℂ  ⊆  ℂ )  →  ( ( 𝐴 (,) 𝐵 ) –cn→ ℂ )  =  ( ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  Cn  ( TopOpen ‘ ℂfld ) ) ) | 
						
							| 39 | 33 34 38 | mp2an | ⊢ ( ( 𝐴 (,) 𝐵 ) –cn→ ℂ )  =  ( ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  Cn  ( TopOpen ‘ ℂfld ) ) | 
						
							| 40 | 5 39 | eleqtrdi | ⊢ ( 𝜑  →  𝐹  ∈  ( ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  Cn  ( TopOpen ‘ ℂfld ) ) ) | 
						
							| 41 | 40 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  𝐹  ∈  ( ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  Cn  ( TopOpen ‘ ℂfld ) ) ) | 
						
							| 42 | 33 | a1i | ⊢ ( 𝜑  →  ( 𝐴 (,) 𝐵 )  ⊆  ℂ ) | 
						
							| 43 |  | resttopon | ⊢ ( ( ( TopOpen ‘ ℂfld )  ∈  ( TopOn ‘ ℂ )  ∧  ( 𝐴 (,) 𝐵 )  ⊆  ℂ )  →  ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  ∈  ( TopOn ‘ ( 𝐴 (,) 𝐵 ) ) ) | 
						
							| 44 | 36 42 43 | sylancr | ⊢ ( 𝜑  →  ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  ∈  ( TopOn ‘ ( 𝐴 (,) 𝐵 ) ) ) | 
						
							| 45 |  | toponuni | ⊢ ( ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  ∈  ( TopOn ‘ ( 𝐴 (,) 𝐵 ) )  →  ( 𝐴 (,) 𝐵 )  =  ∪  ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) ) ) | 
						
							| 46 | 44 45 | syl | ⊢ ( 𝜑  →  ( 𝐴 (,) 𝐵 )  =  ∪  ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) ) ) | 
						
							| 47 | 46 | eleq2d | ⊢ ( 𝜑  →  ( 𝑦  ∈  ( 𝐴 (,) 𝐵 )  ↔  𝑦  ∈  ∪  ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) ) ) ) | 
						
							| 48 | 47 | biimpa | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  𝑦  ∈  ∪  ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) ) ) | 
						
							| 49 |  | eqid | ⊢ ∪  ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  =  ∪  ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 50 | 49 | cncnpi | ⊢ ( ( 𝐹  ∈  ( ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  Cn  ( TopOpen ‘ ℂfld ) )  ∧  𝑦  ∈  ∪  ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) ) )  →  𝐹  ∈  ( ( ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  CnP  ( TopOpen ‘ ℂfld ) ) ‘ 𝑦 ) ) | 
						
							| 51 | 41 48 50 | syl2anc | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  𝐹  ∈  ( ( ( ( TopOpen ‘ ℂfld )  ↾t  ( 𝐴 (,) 𝐵 ) )  CnP  ( TopOpen ‘ ℂfld ) ) ‘ 𝑦 ) ) | 
						
							| 52 | 1 26 27 28 29 30 31 32 51 20 35 21 | ftc1 | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  𝑦 ( ℝ  D  𝐺 ) ( 𝐹 ‘ 𝑦 ) ) | 
						
							| 53 |  | vex | ⊢ 𝑦  ∈  V | 
						
							| 54 |  | fvex | ⊢ ( 𝐹 ‘ 𝑦 )  ∈  V | 
						
							| 55 | 53 54 | breldm | ⊢ ( 𝑦 ( ℝ  D  𝐺 ) ( 𝐹 ‘ 𝑦 )  →  𝑦  ∈  dom  ( ℝ  D  𝐺 ) ) | 
						
							| 56 | 52 55 | syl | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  𝑦  ∈  dom  ( ℝ  D  𝐺 ) ) | 
						
							| 57 | 25 56 | eqelssd | ⊢ ( 𝜑  →  dom  ( ℝ  D  𝐺 )  =  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 58 |  | df-fn | ⊢ ( ( ℝ  D  𝐺 )  Fn  ( 𝐴 (,) 𝐵 )  ↔  ( Fun  ( ℝ  D  𝐺 )  ∧  dom  ( ℝ  D  𝐺 )  =  ( 𝐴 (,) 𝐵 ) ) ) | 
						
							| 59 | 9 57 58 | sylanbrc | ⊢ ( 𝜑  →  ( ℝ  D  𝐺 )  Fn  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 60 | 16 | ffnd | ⊢ ( 𝜑  →  𝐹  Fn  ( 𝐴 (,) 𝐵 ) ) | 
						
							| 61 | 9 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  Fun  ( ℝ  D  𝐺 ) ) | 
						
							| 62 |  | funbrfv | ⊢ ( Fun  ( ℝ  D  𝐺 )  →  ( 𝑦 ( ℝ  D  𝐺 ) ( 𝐹 ‘ 𝑦 )  →  ( ( ℝ  D  𝐺 ) ‘ 𝑦 )  =  ( 𝐹 ‘ 𝑦 ) ) ) | 
						
							| 63 | 61 52 62 | sylc | ⊢ ( ( 𝜑  ∧  𝑦  ∈  ( 𝐴 (,) 𝐵 ) )  →  ( ( ℝ  D  𝐺 ) ‘ 𝑦 )  =  ( 𝐹 ‘ 𝑦 ) ) | 
						
							| 64 | 59 60 63 | eqfnfvd | ⊢ ( 𝜑  →  ( ℝ  D  𝐺 )  =  𝐹 ) |