| Step | Hyp | Ref | Expression | 
						
							| 1 |  | logcn.d | ⊢ 𝐷  =  ( ℂ  ∖  ( -∞ (,] 0 ) ) | 
						
							| 2 |  | logf1o | ⊢ log : ( ℂ  ∖  { 0 } ) –1-1-onto→ ran  log | 
						
							| 3 |  | f1ofun | ⊢ ( log : ( ℂ  ∖  { 0 } ) –1-1-onto→ ran  log  →  Fun  log ) | 
						
							| 4 | 2 3 | ax-mp | ⊢ Fun  log | 
						
							| 5 | 1 | logdmss | ⊢ 𝐷  ⊆  ( ℂ  ∖  { 0 } ) | 
						
							| 6 |  | f1odm | ⊢ ( log : ( ℂ  ∖  { 0 } ) –1-1-onto→ ran  log  →  dom  log  =  ( ℂ  ∖  { 0 } ) ) | 
						
							| 7 | 2 6 | ax-mp | ⊢ dom  log  =  ( ℂ  ∖  { 0 } ) | 
						
							| 8 | 5 7 | sseqtrri | ⊢ 𝐷  ⊆  dom  log | 
						
							| 9 |  | funimass4 | ⊢ ( ( Fun  log  ∧  𝐷  ⊆  dom  log )  →  ( ( log  “  𝐷 )  ⊆  ( ◡ ℑ  “  ( - π (,) π ) )  ↔  ∀ 𝑥  ∈  𝐷 ( log ‘ 𝑥 )  ∈  ( ◡ ℑ  “  ( - π (,) π ) ) ) ) | 
						
							| 10 | 4 8 9 | mp2an | ⊢ ( ( log  “  𝐷 )  ⊆  ( ◡ ℑ  “  ( - π (,) π ) )  ↔  ∀ 𝑥  ∈  𝐷 ( log ‘ 𝑥 )  ∈  ( ◡ ℑ  “  ( - π (,) π ) ) ) | 
						
							| 11 | 1 | ellogdm | ⊢ ( 𝑥  ∈  𝐷  ↔  ( 𝑥  ∈  ℂ  ∧  ( 𝑥  ∈  ℝ  →  𝑥  ∈  ℝ+ ) ) ) | 
						
							| 12 | 11 | simplbi | ⊢ ( 𝑥  ∈  𝐷  →  𝑥  ∈  ℂ ) | 
						
							| 13 | 1 | logdmn0 | ⊢ ( 𝑥  ∈  𝐷  →  𝑥  ≠  0 ) | 
						
							| 14 | 12 13 | logcld | ⊢ ( 𝑥  ∈  𝐷  →  ( log ‘ 𝑥 )  ∈  ℂ ) | 
						
							| 15 | 14 | imcld | ⊢ ( 𝑥  ∈  𝐷  →  ( ℑ ‘ ( log ‘ 𝑥 ) )  ∈  ℝ ) | 
						
							| 16 | 12 13 | logimcld | ⊢ ( 𝑥  ∈  𝐷  →  ( - π  <  ( ℑ ‘ ( log ‘ 𝑥 ) )  ∧  ( ℑ ‘ ( log ‘ 𝑥 ) )  ≤  π ) ) | 
						
							| 17 | 16 | simpld | ⊢ ( 𝑥  ∈  𝐷  →  - π  <  ( ℑ ‘ ( log ‘ 𝑥 ) ) ) | 
						
							| 18 |  | pire | ⊢ π  ∈  ℝ | 
						
							| 19 | 18 | a1i | ⊢ ( 𝑥  ∈  𝐷  →  π  ∈  ℝ ) | 
						
							| 20 | 16 | simprd | ⊢ ( 𝑥  ∈  𝐷  →  ( ℑ ‘ ( log ‘ 𝑥 ) )  ≤  π ) | 
						
							| 21 | 1 | logdmnrp | ⊢ ( 𝑥  ∈  𝐷  →  ¬  - 𝑥  ∈  ℝ+ ) | 
						
							| 22 |  | lognegb | ⊢ ( ( 𝑥  ∈  ℂ  ∧  𝑥  ≠  0 )  →  ( - 𝑥  ∈  ℝ+  ↔  ( ℑ ‘ ( log ‘ 𝑥 ) )  =  π ) ) | 
						
							| 23 | 12 13 22 | syl2anc | ⊢ ( 𝑥  ∈  𝐷  →  ( - 𝑥  ∈  ℝ+  ↔  ( ℑ ‘ ( log ‘ 𝑥 ) )  =  π ) ) | 
						
							| 24 | 23 | necon3bbid | ⊢ ( 𝑥  ∈  𝐷  →  ( ¬  - 𝑥  ∈  ℝ+  ↔  ( ℑ ‘ ( log ‘ 𝑥 ) )  ≠  π ) ) | 
						
							| 25 | 21 24 | mpbid | ⊢ ( 𝑥  ∈  𝐷  →  ( ℑ ‘ ( log ‘ 𝑥 ) )  ≠  π ) | 
						
							| 26 | 25 | necomd | ⊢ ( 𝑥  ∈  𝐷  →  π  ≠  ( ℑ ‘ ( log ‘ 𝑥 ) ) ) | 
						
							| 27 | 15 19 20 26 | leneltd | ⊢ ( 𝑥  ∈  𝐷  →  ( ℑ ‘ ( log ‘ 𝑥 ) )  <  π ) | 
						
							| 28 | 18 | renegcli | ⊢ - π  ∈  ℝ | 
						
							| 29 | 28 | rexri | ⊢ - π  ∈  ℝ* | 
						
							| 30 | 18 | rexri | ⊢ π  ∈  ℝ* | 
						
							| 31 |  | elioo2 | ⊢ ( ( - π  ∈  ℝ*  ∧  π  ∈  ℝ* )  →  ( ( ℑ ‘ ( log ‘ 𝑥 ) )  ∈  ( - π (,) π )  ↔  ( ( ℑ ‘ ( log ‘ 𝑥 ) )  ∈  ℝ  ∧  - π  <  ( ℑ ‘ ( log ‘ 𝑥 ) )  ∧  ( ℑ ‘ ( log ‘ 𝑥 ) )  <  π ) ) ) | 
						
							| 32 | 29 30 31 | mp2an | ⊢ ( ( ℑ ‘ ( log ‘ 𝑥 ) )  ∈  ( - π (,) π )  ↔  ( ( ℑ ‘ ( log ‘ 𝑥 ) )  ∈  ℝ  ∧  - π  <  ( ℑ ‘ ( log ‘ 𝑥 ) )  ∧  ( ℑ ‘ ( log ‘ 𝑥 ) )  <  π ) ) | 
						
							| 33 | 15 17 27 32 | syl3anbrc | ⊢ ( 𝑥  ∈  𝐷  →  ( ℑ ‘ ( log ‘ 𝑥 ) )  ∈  ( - π (,) π ) ) | 
						
							| 34 |  | imf | ⊢ ℑ : ℂ ⟶ ℝ | 
						
							| 35 |  | ffn | ⊢ ( ℑ : ℂ ⟶ ℝ  →  ℑ  Fn  ℂ ) | 
						
							| 36 |  | elpreima | ⊢ ( ℑ  Fn  ℂ  →  ( ( log ‘ 𝑥 )  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ↔  ( ( log ‘ 𝑥 )  ∈  ℂ  ∧  ( ℑ ‘ ( log ‘ 𝑥 ) )  ∈  ( - π (,) π ) ) ) ) | 
						
							| 37 | 34 35 36 | mp2b | ⊢ ( ( log ‘ 𝑥 )  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ↔  ( ( log ‘ 𝑥 )  ∈  ℂ  ∧  ( ℑ ‘ ( log ‘ 𝑥 ) )  ∈  ( - π (,) π ) ) ) | 
						
							| 38 | 14 33 37 | sylanbrc | ⊢ ( 𝑥  ∈  𝐷  →  ( log ‘ 𝑥 )  ∈  ( ◡ ℑ  “  ( - π (,) π ) ) ) | 
						
							| 39 | 10 38 | mprgbir | ⊢ ( log  “  𝐷 )  ⊆  ( ◡ ℑ  “  ( - π (,) π ) ) | 
						
							| 40 |  | df-ioo | ⊢ (,)  =  ( 𝑥  ∈  ℝ* ,  𝑦  ∈  ℝ*  ↦  { 𝑧  ∈  ℝ*  ∣  ( 𝑥  <  𝑧  ∧  𝑧  <  𝑦 ) } ) | 
						
							| 41 |  | df-ioc | ⊢ (,]  =  ( 𝑥  ∈  ℝ* ,  𝑦  ∈  ℝ*  ↦  { 𝑧  ∈  ℝ*  ∣  ( 𝑥  <  𝑧  ∧  𝑧  ≤  𝑦 ) } ) | 
						
							| 42 |  | idd | ⊢ ( ( - π  ∈  ℝ*  ∧  𝑤  ∈  ℝ* )  →  ( - π  <  𝑤  →  - π  <  𝑤 ) ) | 
						
							| 43 |  | xrltle | ⊢ ( ( 𝑤  ∈  ℝ*  ∧  π  ∈  ℝ* )  →  ( 𝑤  <  π  →  𝑤  ≤  π ) ) | 
						
							| 44 | 40 41 42 43 | ixxssixx | ⊢ ( - π (,) π )  ⊆  ( - π (,] π ) | 
						
							| 45 |  | imass2 | ⊢ ( ( - π (,) π )  ⊆  ( - π (,] π )  →  ( ◡ ℑ  “  ( - π (,) π ) )  ⊆  ( ◡ ℑ  “  ( - π (,] π ) ) ) | 
						
							| 46 | 44 45 | ax-mp | ⊢ ( ◡ ℑ  “  ( - π (,) π ) )  ⊆  ( ◡ ℑ  “  ( - π (,] π ) ) | 
						
							| 47 |  | logrn | ⊢ ran  log  =  ( ◡ ℑ  “  ( - π (,] π ) ) | 
						
							| 48 | 46 47 | sseqtrri | ⊢ ( ◡ ℑ  “  ( - π (,) π ) )  ⊆  ran  log | 
						
							| 49 | 48 | sseli | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  𝑥  ∈  ran  log ) | 
						
							| 50 |  | logef | ⊢ ( 𝑥  ∈  ran  log  →  ( log ‘ ( exp ‘ 𝑥 ) )  =  𝑥 ) | 
						
							| 51 | 49 50 | syl | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( log ‘ ( exp ‘ 𝑥 ) )  =  𝑥 ) | 
						
							| 52 |  | elpreima | ⊢ ( ℑ  Fn  ℂ  →  ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ↔  ( 𝑥  ∈  ℂ  ∧  ( ℑ ‘ 𝑥 )  ∈  ( - π (,) π ) ) ) ) | 
						
							| 53 | 34 35 52 | mp2b | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ↔  ( 𝑥  ∈  ℂ  ∧  ( ℑ ‘ 𝑥 )  ∈  ( - π (,) π ) ) ) | 
						
							| 54 |  | efcl | ⊢ ( 𝑥  ∈  ℂ  →  ( exp ‘ 𝑥 )  ∈  ℂ ) | 
						
							| 55 | 54 | adantr | ⊢ ( ( 𝑥  ∈  ℂ  ∧  ( ℑ ‘ 𝑥 )  ∈  ( - π (,) π ) )  →  ( exp ‘ 𝑥 )  ∈  ℂ ) | 
						
							| 56 | 53 55 | sylbi | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( exp ‘ 𝑥 )  ∈  ℂ ) | 
						
							| 57 | 53 | simplbi | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  𝑥  ∈  ℂ ) | 
						
							| 58 | 57 | imcld | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( ℑ ‘ 𝑥 )  ∈  ℝ ) | 
						
							| 59 |  | eliooord | ⊢ ( ( ℑ ‘ 𝑥 )  ∈  ( - π (,) π )  →  ( - π  <  ( ℑ ‘ 𝑥 )  ∧  ( ℑ ‘ 𝑥 )  <  π ) ) | 
						
							| 60 | 53 59 | simplbiim | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( - π  <  ( ℑ ‘ 𝑥 )  ∧  ( ℑ ‘ 𝑥 )  <  π ) ) | 
						
							| 61 | 60 | simprd | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( ℑ ‘ 𝑥 )  <  π ) | 
						
							| 62 | 58 61 | ltned | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( ℑ ‘ 𝑥 )  ≠  π ) | 
						
							| 63 | 51 | adantr | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( log ‘ ( exp ‘ 𝑥 ) )  =  𝑥 ) | 
						
							| 64 | 63 | fveq2d | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( ℑ ‘ ( log ‘ ( exp ‘ 𝑥 ) ) )  =  ( ℑ ‘ 𝑥 ) ) | 
						
							| 65 |  | simpr | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) ) | 
						
							| 66 |  | mnfxr | ⊢ -∞  ∈  ℝ* | 
						
							| 67 |  | 0re | ⊢ 0  ∈  ℝ | 
						
							| 68 |  | elioc2 | ⊢ ( ( -∞  ∈  ℝ*  ∧  0  ∈  ℝ )  →  ( ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 )  ↔  ( ( exp ‘ 𝑥 )  ∈  ℝ  ∧  -∞  <  ( exp ‘ 𝑥 )  ∧  ( exp ‘ 𝑥 )  ≤  0 ) ) ) | 
						
							| 69 | 66 67 68 | mp2an | ⊢ ( ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 )  ↔  ( ( exp ‘ 𝑥 )  ∈  ℝ  ∧  -∞  <  ( exp ‘ 𝑥 )  ∧  ( exp ‘ 𝑥 )  ≤  0 ) ) | 
						
							| 70 | 65 69 | sylib | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( ( exp ‘ 𝑥 )  ∈  ℝ  ∧  -∞  <  ( exp ‘ 𝑥 )  ∧  ( exp ‘ 𝑥 )  ≤  0 ) ) | 
						
							| 71 | 70 | simp1d | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( exp ‘ 𝑥 )  ∈  ℝ ) | 
						
							| 72 |  | 0red | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  0  ∈  ℝ ) | 
						
							| 73 | 70 | simp3d | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( exp ‘ 𝑥 )  ≤  0 ) | 
						
							| 74 |  | efne0 | ⊢ ( 𝑥  ∈  ℂ  →  ( exp ‘ 𝑥 )  ≠  0 ) | 
						
							| 75 | 57 74 | syl | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( exp ‘ 𝑥 )  ≠  0 ) | 
						
							| 76 | 75 | adantr | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( exp ‘ 𝑥 )  ≠  0 ) | 
						
							| 77 | 76 | necomd | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  0  ≠  ( exp ‘ 𝑥 ) ) | 
						
							| 78 | 71 72 73 77 | leneltd | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( exp ‘ 𝑥 )  <  0 ) | 
						
							| 79 | 71 78 | negelrpd | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  - ( exp ‘ 𝑥 )  ∈  ℝ+ ) | 
						
							| 80 |  | lognegb | ⊢ ( ( ( exp ‘ 𝑥 )  ∈  ℂ  ∧  ( exp ‘ 𝑥 )  ≠  0 )  →  ( - ( exp ‘ 𝑥 )  ∈  ℝ+  ↔  ( ℑ ‘ ( log ‘ ( exp ‘ 𝑥 ) ) )  =  π ) ) | 
						
							| 81 | 56 75 80 | syl2anc | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( - ( exp ‘ 𝑥 )  ∈  ℝ+  ↔  ( ℑ ‘ ( log ‘ ( exp ‘ 𝑥 ) ) )  =  π ) ) | 
						
							| 82 | 81 | adantr | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( - ( exp ‘ 𝑥 )  ∈  ℝ+  ↔  ( ℑ ‘ ( log ‘ ( exp ‘ 𝑥 ) ) )  =  π ) ) | 
						
							| 83 | 79 82 | mpbid | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( ℑ ‘ ( log ‘ ( exp ‘ 𝑥 ) ) )  =  π ) | 
						
							| 84 | 64 83 | eqtr3d | ⊢ ( ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  ∧  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) )  →  ( ℑ ‘ 𝑥 )  =  π ) | 
						
							| 85 | 84 | ex | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 )  →  ( ℑ ‘ 𝑥 )  =  π ) ) | 
						
							| 86 | 85 | necon3ad | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( ( ℑ ‘ 𝑥 )  ≠  π  →  ¬  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) ) ) | 
						
							| 87 | 62 86 | mpd | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ¬  ( exp ‘ 𝑥 )  ∈  ( -∞ (,] 0 ) ) | 
						
							| 88 | 56 87 | eldifd | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( exp ‘ 𝑥 )  ∈  ( ℂ  ∖  ( -∞ (,] 0 ) ) ) | 
						
							| 89 | 88 1 | eleqtrrdi | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( exp ‘ 𝑥 )  ∈  𝐷 ) | 
						
							| 90 |  | funfvima2 | ⊢ ( ( Fun  log  ∧  𝐷  ⊆  dom  log )  →  ( ( exp ‘ 𝑥 )  ∈  𝐷  →  ( log ‘ ( exp ‘ 𝑥 ) )  ∈  ( log  “  𝐷 ) ) ) | 
						
							| 91 | 4 8 90 | mp2an | ⊢ ( ( exp ‘ 𝑥 )  ∈  𝐷  →  ( log ‘ ( exp ‘ 𝑥 ) )  ∈  ( log  “  𝐷 ) ) | 
						
							| 92 | 89 91 | syl | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  ( log ‘ ( exp ‘ 𝑥 ) )  ∈  ( log  “  𝐷 ) ) | 
						
							| 93 | 51 92 | eqeltrrd | ⊢ ( 𝑥  ∈  ( ◡ ℑ  “  ( - π (,) π ) )  →  𝑥  ∈  ( log  “  𝐷 ) ) | 
						
							| 94 | 93 | ssriv | ⊢ ( ◡ ℑ  “  ( - π (,) π ) )  ⊆  ( log  “  𝐷 ) | 
						
							| 95 | 39 94 | eqssi | ⊢ ( log  “  𝐷 )  =  ( ◡ ℑ  “  ( - π (,) π ) ) | 
						
							| 96 |  | imcncf | ⊢ ℑ  ∈  ( ℂ –cn→ ℝ ) | 
						
							| 97 |  | ssid | ⊢ ℂ  ⊆  ℂ | 
						
							| 98 |  | ax-resscn | ⊢ ℝ  ⊆  ℂ | 
						
							| 99 |  | eqid | ⊢ ( TopOpen ‘ ℂfld )  =  ( TopOpen ‘ ℂfld ) | 
						
							| 100 | 99 | cnfldtopon | ⊢ ( TopOpen ‘ ℂfld )  ∈  ( TopOn ‘ ℂ ) | 
						
							| 101 | 100 | toponrestid | ⊢ ( TopOpen ‘ ℂfld )  =  ( ( TopOpen ‘ ℂfld )  ↾t  ℂ ) | 
						
							| 102 |  | tgioo4 | ⊢ ( topGen ‘ ran  (,) )  =  ( ( TopOpen ‘ ℂfld )  ↾t  ℝ ) | 
						
							| 103 | 99 101 102 | cncfcn | ⊢ ( ( ℂ  ⊆  ℂ  ∧  ℝ  ⊆  ℂ )  →  ( ℂ –cn→ ℝ )  =  ( ( TopOpen ‘ ℂfld )  Cn  ( topGen ‘ ran  (,) ) ) ) | 
						
							| 104 | 97 98 103 | mp2an | ⊢ ( ℂ –cn→ ℝ )  =  ( ( TopOpen ‘ ℂfld )  Cn  ( topGen ‘ ran  (,) ) ) | 
						
							| 105 | 96 104 | eleqtri | ⊢ ℑ  ∈  ( ( TopOpen ‘ ℂfld )  Cn  ( topGen ‘ ran  (,) ) ) | 
						
							| 106 |  | iooretop | ⊢ ( - π (,) π )  ∈  ( topGen ‘ ran  (,) ) | 
						
							| 107 |  | cnima | ⊢ ( ( ℑ  ∈  ( ( TopOpen ‘ ℂfld )  Cn  ( topGen ‘ ran  (,) ) )  ∧  ( - π (,) π )  ∈  ( topGen ‘ ran  (,) ) )  →  ( ◡ ℑ  “  ( - π (,) π ) )  ∈  ( TopOpen ‘ ℂfld ) ) | 
						
							| 108 | 105 106 107 | mp2an | ⊢ ( ◡ ℑ  “  ( - π (,) π ) )  ∈  ( TopOpen ‘ ℂfld ) | 
						
							| 109 | 95 108 | eqeltri | ⊢ ( log  “  𝐷 )  ∈  ( TopOpen ‘ ℂfld ) |