| Step | Hyp | Ref | Expression | 
						
							| 1 |  | sinval | ⊢ ( 𝐴  ∈  ℂ  →  ( sin ‘ 𝐴 )  =  ( ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  /  ( 2  ·  i ) ) ) | 
						
							| 2 | 1 | eqeq1d | ⊢ ( 𝐴  ∈  ℂ  →  ( ( sin ‘ 𝐴 )  =  0  ↔  ( ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  /  ( 2  ·  i ) )  =  0 ) ) | 
						
							| 3 |  | ax-icn | ⊢ i  ∈  ℂ | 
						
							| 4 |  | mulcl | ⊢ ( ( i  ∈  ℂ  ∧  𝐴  ∈  ℂ )  →  ( i  ·  𝐴 )  ∈  ℂ ) | 
						
							| 5 | 3 4 | mpan | ⊢ ( 𝐴  ∈  ℂ  →  ( i  ·  𝐴 )  ∈  ℂ ) | 
						
							| 6 |  | efcl | ⊢ ( ( i  ·  𝐴 )  ∈  ℂ  →  ( exp ‘ ( i  ·  𝐴 ) )  ∈  ℂ ) | 
						
							| 7 | 5 6 | syl | ⊢ ( 𝐴  ∈  ℂ  →  ( exp ‘ ( i  ·  𝐴 ) )  ∈  ℂ ) | 
						
							| 8 |  | negicn | ⊢ - i  ∈  ℂ | 
						
							| 9 |  | mulcl | ⊢ ( ( - i  ∈  ℂ  ∧  𝐴  ∈  ℂ )  →  ( - i  ·  𝐴 )  ∈  ℂ ) | 
						
							| 10 | 8 9 | mpan | ⊢ ( 𝐴  ∈  ℂ  →  ( - i  ·  𝐴 )  ∈  ℂ ) | 
						
							| 11 |  | efcl | ⊢ ( ( - i  ·  𝐴 )  ∈  ℂ  →  ( exp ‘ ( - i  ·  𝐴 ) )  ∈  ℂ ) | 
						
							| 12 | 10 11 | syl | ⊢ ( 𝐴  ∈  ℂ  →  ( exp ‘ ( - i  ·  𝐴 ) )  ∈  ℂ ) | 
						
							| 13 | 7 12 | subcld | ⊢ ( 𝐴  ∈  ℂ  →  ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  ∈  ℂ ) | 
						
							| 14 |  | 2mulicn | ⊢ ( 2  ·  i )  ∈  ℂ | 
						
							| 15 |  | 2muline0 | ⊢ ( 2  ·  i )  ≠  0 | 
						
							| 16 |  | diveq0 | ⊢ ( ( ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  ∈  ℂ  ∧  ( 2  ·  i )  ∈  ℂ  ∧  ( 2  ·  i )  ≠  0 )  →  ( ( ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  /  ( 2  ·  i ) )  =  0  ↔  ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  =  0 ) ) | 
						
							| 17 | 14 15 16 | mp3an23 | ⊢ ( ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  ∈  ℂ  →  ( ( ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  /  ( 2  ·  i ) )  =  0  ↔  ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  =  0 ) ) | 
						
							| 18 | 13 17 | syl | ⊢ ( 𝐴  ∈  ℂ  →  ( ( ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  /  ( 2  ·  i ) )  =  0  ↔  ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  =  0 ) ) | 
						
							| 19 | 7 12 | subeq0ad | ⊢ ( 𝐴  ∈  ℂ  →  ( ( ( exp ‘ ( i  ·  𝐴 ) )  −  ( exp ‘ ( - i  ·  𝐴 ) ) )  =  0  ↔  ( exp ‘ ( i  ·  𝐴 ) )  =  ( exp ‘ ( - i  ·  𝐴 ) ) ) ) | 
						
							| 20 | 2 18 19 | 3bitrd | ⊢ ( 𝐴  ∈  ℂ  →  ( ( sin ‘ 𝐴 )  =  0  ↔  ( exp ‘ ( i  ·  𝐴 ) )  =  ( exp ‘ ( - i  ·  𝐴 ) ) ) ) | 
						
							| 21 |  | oveq2 | ⊢ ( ( exp ‘ ( i  ·  𝐴 ) )  =  ( exp ‘ ( - i  ·  𝐴 ) )  →  ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( i  ·  𝐴 ) ) )  =  ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( - i  ·  𝐴 ) ) ) ) | 
						
							| 22 |  | 2cn | ⊢ 2  ∈  ℂ | 
						
							| 23 |  | mul12 | ⊢ ( ( i  ∈  ℂ  ∧  2  ∈  ℂ  ∧  𝐴  ∈  ℂ )  →  ( i  ·  ( 2  ·  𝐴 ) )  =  ( 2  ·  ( i  ·  𝐴 ) ) ) | 
						
							| 24 | 3 22 23 | mp3an12 | ⊢ ( 𝐴  ∈  ℂ  →  ( i  ·  ( 2  ·  𝐴 ) )  =  ( 2  ·  ( i  ·  𝐴 ) ) ) | 
						
							| 25 | 5 | 2timesd | ⊢ ( 𝐴  ∈  ℂ  →  ( 2  ·  ( i  ·  𝐴 ) )  =  ( ( i  ·  𝐴 )  +  ( i  ·  𝐴 ) ) ) | 
						
							| 26 | 24 25 | eqtrd | ⊢ ( 𝐴  ∈  ℂ  →  ( i  ·  ( 2  ·  𝐴 ) )  =  ( ( i  ·  𝐴 )  +  ( i  ·  𝐴 ) ) ) | 
						
							| 27 | 26 | fveq2d | ⊢ ( 𝐴  ∈  ℂ  →  ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) )  =  ( exp ‘ ( ( i  ·  𝐴 )  +  ( i  ·  𝐴 ) ) ) ) | 
						
							| 28 |  | efadd | ⊢ ( ( ( i  ·  𝐴 )  ∈  ℂ  ∧  ( i  ·  𝐴 )  ∈  ℂ )  →  ( exp ‘ ( ( i  ·  𝐴 )  +  ( i  ·  𝐴 ) ) )  =  ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( i  ·  𝐴 ) ) ) ) | 
						
							| 29 | 5 5 28 | syl2anc | ⊢ ( 𝐴  ∈  ℂ  →  ( exp ‘ ( ( i  ·  𝐴 )  +  ( i  ·  𝐴 ) ) )  =  ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( i  ·  𝐴 ) ) ) ) | 
						
							| 30 | 27 29 | eqtr2d | ⊢ ( 𝐴  ∈  ℂ  →  ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( i  ·  𝐴 ) ) )  =  ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) ) | 
						
							| 31 |  | efadd | ⊢ ( ( ( i  ·  𝐴 )  ∈  ℂ  ∧  ( - i  ·  𝐴 )  ∈  ℂ )  →  ( exp ‘ ( ( i  ·  𝐴 )  +  ( - i  ·  𝐴 ) ) )  =  ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( - i  ·  𝐴 ) ) ) ) | 
						
							| 32 | 5 10 31 | syl2anc | ⊢ ( 𝐴  ∈  ℂ  →  ( exp ‘ ( ( i  ·  𝐴 )  +  ( - i  ·  𝐴 ) ) )  =  ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( - i  ·  𝐴 ) ) ) ) | 
						
							| 33 | 3 | negidi | ⊢ ( i  +  - i )  =  0 | 
						
							| 34 | 33 | oveq1i | ⊢ ( ( i  +  - i )  ·  𝐴 )  =  ( 0  ·  𝐴 ) | 
						
							| 35 |  | adddir | ⊢ ( ( i  ∈  ℂ  ∧  - i  ∈  ℂ  ∧  𝐴  ∈  ℂ )  →  ( ( i  +  - i )  ·  𝐴 )  =  ( ( i  ·  𝐴 )  +  ( - i  ·  𝐴 ) ) ) | 
						
							| 36 | 3 8 35 | mp3an12 | ⊢ ( 𝐴  ∈  ℂ  →  ( ( i  +  - i )  ·  𝐴 )  =  ( ( i  ·  𝐴 )  +  ( - i  ·  𝐴 ) ) ) | 
						
							| 37 |  | mul02 | ⊢ ( 𝐴  ∈  ℂ  →  ( 0  ·  𝐴 )  =  0 ) | 
						
							| 38 | 34 36 37 | 3eqtr3a | ⊢ ( 𝐴  ∈  ℂ  →  ( ( i  ·  𝐴 )  +  ( - i  ·  𝐴 ) )  =  0 ) | 
						
							| 39 | 38 | fveq2d | ⊢ ( 𝐴  ∈  ℂ  →  ( exp ‘ ( ( i  ·  𝐴 )  +  ( - i  ·  𝐴 ) ) )  =  ( exp ‘ 0 ) ) | 
						
							| 40 |  | ef0 | ⊢ ( exp ‘ 0 )  =  1 | 
						
							| 41 | 39 40 | eqtrdi | ⊢ ( 𝐴  ∈  ℂ  →  ( exp ‘ ( ( i  ·  𝐴 )  +  ( - i  ·  𝐴 ) ) )  =  1 ) | 
						
							| 42 | 32 41 | eqtr3d | ⊢ ( 𝐴  ∈  ℂ  →  ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( - i  ·  𝐴 ) ) )  =  1 ) | 
						
							| 43 | 30 42 | eqeq12d | ⊢ ( 𝐴  ∈  ℂ  →  ( ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( i  ·  𝐴 ) ) )  =  ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( - i  ·  𝐴 ) ) )  ↔  ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) )  =  1 ) ) | 
						
							| 44 |  | fveq2 | ⊢ ( ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) )  =  1  →  ( abs ‘ ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) )  =  ( abs ‘ 1 ) ) | 
						
							| 45 | 43 44 | biimtrdi | ⊢ ( 𝐴  ∈  ℂ  →  ( ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( i  ·  𝐴 ) ) )  =  ( ( exp ‘ ( i  ·  𝐴 ) )  ·  ( exp ‘ ( - i  ·  𝐴 ) ) )  →  ( abs ‘ ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) )  =  ( abs ‘ 1 ) ) ) | 
						
							| 46 | 21 45 | syl5 | ⊢ ( 𝐴  ∈  ℂ  →  ( ( exp ‘ ( i  ·  𝐴 ) )  =  ( exp ‘ ( - i  ·  𝐴 ) )  →  ( abs ‘ ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) )  =  ( abs ‘ 1 ) ) ) | 
						
							| 47 | 20 46 | sylbid | ⊢ ( 𝐴  ∈  ℂ  →  ( ( sin ‘ 𝐴 )  =  0  →  ( abs ‘ ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) )  =  ( abs ‘ 1 ) ) ) | 
						
							| 48 |  | abs1 | ⊢ ( abs ‘ 1 )  =  1 | 
						
							| 49 | 48 | eqeq2i | ⊢ ( ( abs ‘ ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) )  =  ( abs ‘ 1 )  ↔  ( abs ‘ ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) )  =  1 ) | 
						
							| 50 |  | 2re | ⊢ 2  ∈  ℝ | 
						
							| 51 |  | 2ne0 | ⊢ 2  ≠  0 | 
						
							| 52 |  | mulre | ⊢ ( ( 𝐴  ∈  ℂ  ∧  2  ∈  ℝ  ∧  2  ≠  0 )  →  ( 𝐴  ∈  ℝ  ↔  ( 2  ·  𝐴 )  ∈  ℝ ) ) | 
						
							| 53 | 50 51 52 | mp3an23 | ⊢ ( 𝐴  ∈  ℂ  →  ( 𝐴  ∈  ℝ  ↔  ( 2  ·  𝐴 )  ∈  ℝ ) ) | 
						
							| 54 |  | mulcl | ⊢ ( ( 2  ∈  ℂ  ∧  𝐴  ∈  ℂ )  →  ( 2  ·  𝐴 )  ∈  ℂ ) | 
						
							| 55 | 22 54 | mpan | ⊢ ( 𝐴  ∈  ℂ  →  ( 2  ·  𝐴 )  ∈  ℂ ) | 
						
							| 56 |  | absefib | ⊢ ( ( 2  ·  𝐴 )  ∈  ℂ  →  ( ( 2  ·  𝐴 )  ∈  ℝ  ↔  ( abs ‘ ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) )  =  1 ) ) | 
						
							| 57 | 55 56 | syl | ⊢ ( 𝐴  ∈  ℂ  →  ( ( 2  ·  𝐴 )  ∈  ℝ  ↔  ( abs ‘ ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) )  =  1 ) ) | 
						
							| 58 | 53 57 | bitr2d | ⊢ ( 𝐴  ∈  ℂ  →  ( ( abs ‘ ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) )  =  1  ↔  𝐴  ∈  ℝ ) ) | 
						
							| 59 | 49 58 | bitrid | ⊢ ( 𝐴  ∈  ℂ  →  ( ( abs ‘ ( exp ‘ ( i  ·  ( 2  ·  𝐴 ) ) ) )  =  ( abs ‘ 1 )  ↔  𝐴  ∈  ℝ ) ) | 
						
							| 60 | 47 59 | sylibd | ⊢ ( 𝐴  ∈  ℂ  →  ( ( sin ‘ 𝐴 )  =  0  →  𝐴  ∈  ℝ ) ) | 
						
							| 61 | 60 | imp | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  𝐴  ∈  ℝ ) | 
						
							| 62 |  | pirp | ⊢ π  ∈  ℝ+ | 
						
							| 63 |  | modval | ⊢ ( ( 𝐴  ∈  ℝ  ∧  π  ∈  ℝ+ )  →  ( 𝐴  mod  π )  =  ( 𝐴  −  ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) ) ) ) | 
						
							| 64 | 61 62 63 | sylancl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 𝐴  mod  π )  =  ( 𝐴  −  ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) ) ) ) | 
						
							| 65 |  | picn | ⊢ π  ∈  ℂ | 
						
							| 66 |  | pire | ⊢ π  ∈  ℝ | 
						
							| 67 |  | pipos | ⊢ 0  <  π | 
						
							| 68 | 66 67 | gt0ne0ii | ⊢ π  ≠  0 | 
						
							| 69 |  | redivcl | ⊢ ( ( 𝐴  ∈  ℝ  ∧  π  ∈  ℝ  ∧  π  ≠  0 )  →  ( 𝐴  /  π )  ∈  ℝ ) | 
						
							| 70 | 66 68 69 | mp3an23 | ⊢ ( 𝐴  ∈  ℝ  →  ( 𝐴  /  π )  ∈  ℝ ) | 
						
							| 71 | 61 70 | syl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 𝐴  /  π )  ∈  ℝ ) | 
						
							| 72 | 71 | flcld | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( ⌊ ‘ ( 𝐴  /  π ) )  ∈  ℤ ) | 
						
							| 73 | 72 | zcnd | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( ⌊ ‘ ( 𝐴  /  π ) )  ∈  ℂ ) | 
						
							| 74 |  | mulcl | ⊢ ( ( π  ∈  ℂ  ∧  ( ⌊ ‘ ( 𝐴  /  π ) )  ∈  ℂ )  →  ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) )  ∈  ℂ ) | 
						
							| 75 | 65 73 74 | sylancr | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) )  ∈  ℂ ) | 
						
							| 76 |  | negsub | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) )  ∈  ℂ )  →  ( 𝐴  +  - ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) ) )  =  ( 𝐴  −  ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) ) ) ) | 
						
							| 77 | 75 76 | syldan | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 𝐴  +  - ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) ) )  =  ( 𝐴  −  ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) ) ) ) | 
						
							| 78 |  | mulcom | ⊢ ( ( π  ∈  ℂ  ∧  ( ⌊ ‘ ( 𝐴  /  π ) )  ∈  ℂ )  →  ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) )  =  ( ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) | 
						
							| 79 | 65 73 78 | sylancr | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) )  =  ( ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) | 
						
							| 80 | 79 | negeqd | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  - ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) )  =  - ( ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) | 
						
							| 81 |  | mulneg1 | ⊢ ( ( ( ⌊ ‘ ( 𝐴  /  π ) )  ∈  ℂ  ∧  π  ∈  ℂ )  →  ( - ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π )  =  - ( ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) | 
						
							| 82 | 73 65 81 | sylancl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( - ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π )  =  - ( ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) | 
						
							| 83 | 80 82 | eqtr4d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  - ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) )  =  ( - ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) | 
						
							| 84 | 83 | oveq2d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 𝐴  +  - ( π  ·  ( ⌊ ‘ ( 𝐴  /  π ) ) ) )  =  ( 𝐴  +  ( - ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) ) | 
						
							| 85 | 64 77 84 | 3eqtr2d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 𝐴  mod  π )  =  ( 𝐴  +  ( - ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) ) | 
						
							| 86 | 85 | fveq2d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( sin ‘ ( 𝐴  mod  π ) )  =  ( sin ‘ ( 𝐴  +  ( - ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) ) ) | 
						
							| 87 | 86 | fveq2d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) )  =  ( abs ‘ ( sin ‘ ( 𝐴  +  ( - ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) ) ) ) | 
						
							| 88 | 72 | znegcld | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  - ( ⌊ ‘ ( 𝐴  /  π ) )  ∈  ℤ ) | 
						
							| 89 |  | abssinper | ⊢ ( ( 𝐴  ∈  ℂ  ∧  - ( ⌊ ‘ ( 𝐴  /  π ) )  ∈  ℤ )  →  ( abs ‘ ( sin ‘ ( 𝐴  +  ( - ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) ) )  =  ( abs ‘ ( sin ‘ 𝐴 ) ) ) | 
						
							| 90 | 88 89 | syldan | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( abs ‘ ( sin ‘ ( 𝐴  +  ( - ( ⌊ ‘ ( 𝐴  /  π ) )  ·  π ) ) ) )  =  ( abs ‘ ( sin ‘ 𝐴 ) ) ) | 
						
							| 91 |  | simpr | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( sin ‘ 𝐴 )  =  0 ) | 
						
							| 92 | 91 | fveq2d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( abs ‘ ( sin ‘ 𝐴 ) )  =  ( abs ‘ 0 ) ) | 
						
							| 93 | 87 90 92 | 3eqtrd | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) )  =  ( abs ‘ 0 ) ) | 
						
							| 94 |  | abs0 | ⊢ ( abs ‘ 0 )  =  0 | 
						
							| 95 | 93 94 | eqtrdi | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) )  =  0 ) | 
						
							| 96 |  | modcl | ⊢ ( ( 𝐴  ∈  ℝ  ∧  π  ∈  ℝ+ )  →  ( 𝐴  mod  π )  ∈  ℝ ) | 
						
							| 97 | 61 62 96 | sylancl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 𝐴  mod  π )  ∈  ℝ ) | 
						
							| 98 |  | modlt | ⊢ ( ( 𝐴  ∈  ℝ  ∧  π  ∈  ℝ+ )  →  ( 𝐴  mod  π )  <  π ) | 
						
							| 99 | 61 62 98 | sylancl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 𝐴  mod  π )  <  π ) | 
						
							| 100 | 97 99 | jca | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( ( 𝐴  mod  π )  ∈  ℝ  ∧  ( 𝐴  mod  π )  <  π ) ) | 
						
							| 101 | 100 | biantrurd | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 0  <  ( 𝐴  mod  π )  ↔  ( ( ( 𝐴  mod  π )  ∈  ℝ  ∧  ( 𝐴  mod  π )  <  π )  ∧  0  <  ( 𝐴  mod  π ) ) ) ) | 
						
							| 102 |  | 0re | ⊢ 0  ∈  ℝ | 
						
							| 103 |  | rexr | ⊢ ( 0  ∈  ℝ  →  0  ∈  ℝ* ) | 
						
							| 104 |  | rexr | ⊢ ( π  ∈  ℝ  →  π  ∈  ℝ* ) | 
						
							| 105 |  | elioo2 | ⊢ ( ( 0  ∈  ℝ*  ∧  π  ∈  ℝ* )  →  ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  ↔  ( ( 𝐴  mod  π )  ∈  ℝ  ∧  0  <  ( 𝐴  mod  π )  ∧  ( 𝐴  mod  π )  <  π ) ) ) | 
						
							| 106 | 103 104 105 | syl2an | ⊢ ( ( 0  ∈  ℝ  ∧  π  ∈  ℝ )  →  ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  ↔  ( ( 𝐴  mod  π )  ∈  ℝ  ∧  0  <  ( 𝐴  mod  π )  ∧  ( 𝐴  mod  π )  <  π ) ) ) | 
						
							| 107 | 102 66 106 | mp2an | ⊢ ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  ↔  ( ( 𝐴  mod  π )  ∈  ℝ  ∧  0  <  ( 𝐴  mod  π )  ∧  ( 𝐴  mod  π )  <  π ) ) | 
						
							| 108 |  | 3anan32 | ⊢ ( ( ( 𝐴  mod  π )  ∈  ℝ  ∧  0  <  ( 𝐴  mod  π )  ∧  ( 𝐴  mod  π )  <  π )  ↔  ( ( ( 𝐴  mod  π )  ∈  ℝ  ∧  ( 𝐴  mod  π )  <  π )  ∧  0  <  ( 𝐴  mod  π ) ) ) | 
						
							| 109 | 107 108 | bitri | ⊢ ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  ↔  ( ( ( 𝐴  mod  π )  ∈  ℝ  ∧  ( 𝐴  mod  π )  <  π )  ∧  0  <  ( 𝐴  mod  π ) ) ) | 
						
							| 110 | 101 109 | bitr4di | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 0  <  ( 𝐴  mod  π )  ↔  ( 𝐴  mod  π )  ∈  ( 0 (,) π ) ) ) | 
						
							| 111 |  | sinq12gt0 | ⊢ ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  →  0  <  ( sin ‘ ( 𝐴  mod  π ) ) ) | 
						
							| 112 |  | elioore | ⊢ ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  →  ( 𝐴  mod  π )  ∈  ℝ ) | 
						
							| 113 | 112 | resincld | ⊢ ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  →  ( sin ‘ ( 𝐴  mod  π ) )  ∈  ℝ ) | 
						
							| 114 |  | ltle | ⊢ ( ( 0  ∈  ℝ  ∧  ( sin ‘ ( 𝐴  mod  π ) )  ∈  ℝ )  →  ( 0  <  ( sin ‘ ( 𝐴  mod  π ) )  →  0  ≤  ( sin ‘ ( 𝐴  mod  π ) ) ) ) | 
						
							| 115 | 102 113 114 | sylancr | ⊢ ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  →  ( 0  <  ( sin ‘ ( 𝐴  mod  π ) )  →  0  ≤  ( sin ‘ ( 𝐴  mod  π ) ) ) ) | 
						
							| 116 | 111 115 | mpd | ⊢ ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  →  0  ≤  ( sin ‘ ( 𝐴  mod  π ) ) ) | 
						
							| 117 | 113 116 | absidd | ⊢ ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  →  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) )  =  ( sin ‘ ( 𝐴  mod  π ) ) ) | 
						
							| 118 | 111 117 | breqtrrd | ⊢ ( ( 𝐴  mod  π )  ∈  ( 0 (,) π )  →  0  <  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) ) ) | 
						
							| 119 | 110 118 | biimtrdi | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 0  <  ( 𝐴  mod  π )  →  0  <  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) ) ) ) | 
						
							| 120 |  | ltne | ⊢ ( ( 0  ∈  ℝ  ∧  0  <  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) ) )  →  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) )  ≠  0 ) | 
						
							| 121 | 102 120 | mpan | ⊢ ( 0  <  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) )  →  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) )  ≠  0 ) | 
						
							| 122 | 119 121 | syl6 | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 0  <  ( 𝐴  mod  π )  →  ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) )  ≠  0 ) ) | 
						
							| 123 | 122 | necon2bd | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( ( abs ‘ ( sin ‘ ( 𝐴  mod  π ) ) )  =  0  →  ¬  0  <  ( 𝐴  mod  π ) ) ) | 
						
							| 124 | 95 123 | mpd | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ¬  0  <  ( 𝐴  mod  π ) ) | 
						
							| 125 |  | modge0 | ⊢ ( ( 𝐴  ∈  ℝ  ∧  π  ∈  ℝ+ )  →  0  ≤  ( 𝐴  mod  π ) ) | 
						
							| 126 | 61 62 125 | sylancl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  0  ≤  ( 𝐴  mod  π ) ) | 
						
							| 127 |  | leloe | ⊢ ( ( 0  ∈  ℝ  ∧  ( 𝐴  mod  π )  ∈  ℝ )  →  ( 0  ≤  ( 𝐴  mod  π )  ↔  ( 0  <  ( 𝐴  mod  π )  ∨  0  =  ( 𝐴  mod  π ) ) ) ) | 
						
							| 128 | 102 97 127 | sylancr | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 0  ≤  ( 𝐴  mod  π )  ↔  ( 0  <  ( 𝐴  mod  π )  ∨  0  =  ( 𝐴  mod  π ) ) ) ) | 
						
							| 129 | 126 128 | mpbid | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 0  <  ( 𝐴  mod  π )  ∨  0  =  ( 𝐴  mod  π ) ) ) | 
						
							| 130 | 129 | ord | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( ¬  0  <  ( 𝐴  mod  π )  →  0  =  ( 𝐴  mod  π ) ) ) | 
						
							| 131 | 124 130 | mpd | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  0  =  ( 𝐴  mod  π ) ) | 
						
							| 132 | 131 | eqcomd | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 𝐴  mod  π )  =  0 ) | 
						
							| 133 |  | mod0 | ⊢ ( ( 𝐴  ∈  ℝ  ∧  π  ∈  ℝ+ )  →  ( ( 𝐴  mod  π )  =  0  ↔  ( 𝐴  /  π )  ∈  ℤ ) ) | 
						
							| 134 | 61 62 133 | sylancl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( ( 𝐴  mod  π )  =  0  ↔  ( 𝐴  /  π )  ∈  ℤ ) ) | 
						
							| 135 | 132 134 | mpbid | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( sin ‘ 𝐴 )  =  0 )  →  ( 𝐴  /  π )  ∈  ℤ ) | 
						
							| 136 |  | divcan1 | ⊢ ( ( 𝐴  ∈  ℂ  ∧  π  ∈  ℂ  ∧  π  ≠  0 )  →  ( ( 𝐴  /  π )  ·  π )  =  𝐴 ) | 
						
							| 137 | 65 68 136 | mp3an23 | ⊢ ( 𝐴  ∈  ℂ  →  ( ( 𝐴  /  π )  ·  π )  =  𝐴 ) | 
						
							| 138 | 137 | fveq2d | ⊢ ( 𝐴  ∈  ℂ  →  ( sin ‘ ( ( 𝐴  /  π )  ·  π ) )  =  ( sin ‘ 𝐴 ) ) | 
						
							| 139 |  | sinkpi | ⊢ ( ( 𝐴  /  π )  ∈  ℤ  →  ( sin ‘ ( ( 𝐴  /  π )  ·  π ) )  =  0 ) | 
						
							| 140 | 138 139 | sylan9req | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( 𝐴  /  π )  ∈  ℤ )  →  ( sin ‘ 𝐴 )  =  0 ) | 
						
							| 141 | 135 140 | impbida | ⊢ ( 𝐴  ∈  ℂ  →  ( ( sin ‘ 𝐴 )  =  0  ↔  ( 𝐴  /  π )  ∈  ℤ ) ) |