| Step | Hyp | Ref | Expression | 
						
							| 1 |  | abscl | ⊢ ( 𝐴  ∈  ℂ  →  ( abs ‘ 𝐴 )  ∈  ℝ ) | 
						
							| 2 | 1 | recnd | ⊢ ( 𝐴  ∈  ℂ  →  ( abs ‘ 𝐴 )  ∈  ℂ ) | 
						
							| 3 |  | subneg | ⊢ ( ( ( abs ‘ 𝐴 )  ∈  ℂ  ∧  𝐴  ∈  ℂ )  →  ( ( abs ‘ 𝐴 )  −  - 𝐴 )  =  ( ( abs ‘ 𝐴 )  +  𝐴 ) ) | 
						
							| 4 | 2 3 | mpancom | ⊢ ( 𝐴  ∈  ℂ  →  ( ( abs ‘ 𝐴 )  −  - 𝐴 )  =  ( ( abs ‘ 𝐴 )  +  𝐴 ) ) | 
						
							| 5 | 4 | eqeq1d | ⊢ ( 𝐴  ∈  ℂ  →  ( ( ( abs ‘ 𝐴 )  −  - 𝐴 )  =  0  ↔  ( ( abs ‘ 𝐴 )  +  𝐴 )  =  0 ) ) | 
						
							| 6 |  | negcl | ⊢ ( 𝐴  ∈  ℂ  →  - 𝐴  ∈  ℂ ) | 
						
							| 7 | 2 6 | subeq0ad | ⊢ ( 𝐴  ∈  ℂ  →  ( ( ( abs ‘ 𝐴 )  −  - 𝐴 )  =  0  ↔  ( abs ‘ 𝐴 )  =  - 𝐴 ) ) | 
						
							| 8 | 5 7 | bitr3d | ⊢ ( 𝐴  ∈  ℂ  →  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  =  0  ↔  ( abs ‘ 𝐴 )  =  - 𝐴 ) ) | 
						
							| 9 |  | ax-icn | ⊢ i  ∈  ℂ | 
						
							| 10 |  | absge0 | ⊢ ( 𝐴  ∈  ℂ  →  0  ≤  ( abs ‘ 𝐴 ) ) | 
						
							| 11 | 1 10 | jca | ⊢ ( 𝐴  ∈  ℂ  →  ( ( abs ‘ 𝐴 )  ∈  ℝ  ∧  0  ≤  ( abs ‘ 𝐴 ) ) ) | 
						
							| 12 |  | eleq1 | ⊢ ( ( abs ‘ 𝐴 )  =  - 𝐴  →  ( ( abs ‘ 𝐴 )  ∈  ℝ  ↔  - 𝐴  ∈  ℝ ) ) | 
						
							| 13 |  | breq2 | ⊢ ( ( abs ‘ 𝐴 )  =  - 𝐴  →  ( 0  ≤  ( abs ‘ 𝐴 )  ↔  0  ≤  - 𝐴 ) ) | 
						
							| 14 | 12 13 | anbi12d | ⊢ ( ( abs ‘ 𝐴 )  =  - 𝐴  →  ( ( ( abs ‘ 𝐴 )  ∈  ℝ  ∧  0  ≤  ( abs ‘ 𝐴 ) )  ↔  ( - 𝐴  ∈  ℝ  ∧  0  ≤  - 𝐴 ) ) ) | 
						
							| 15 | 11 14 | imbitrid | ⊢ ( ( abs ‘ 𝐴 )  =  - 𝐴  →  ( 𝐴  ∈  ℂ  →  ( - 𝐴  ∈  ℝ  ∧  0  ≤  - 𝐴 ) ) ) | 
						
							| 16 | 15 | impcom | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( abs ‘ 𝐴 )  =  - 𝐴 )  →  ( - 𝐴  ∈  ℝ  ∧  0  ≤  - 𝐴 ) ) | 
						
							| 17 |  | resqrtcl | ⊢ ( ( - 𝐴  ∈  ℝ  ∧  0  ≤  - 𝐴 )  →  ( √ ‘ - 𝐴 )  ∈  ℝ ) | 
						
							| 18 | 16 17 | syl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( abs ‘ 𝐴 )  =  - 𝐴 )  →  ( √ ‘ - 𝐴 )  ∈  ℝ ) | 
						
							| 19 | 18 | recnd | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( abs ‘ 𝐴 )  =  - 𝐴 )  →  ( √ ‘ - 𝐴 )  ∈  ℂ ) | 
						
							| 20 |  | mulcl | ⊢ ( ( i  ∈  ℂ  ∧  ( √ ‘ - 𝐴 )  ∈  ℂ )  →  ( i  ·  ( √ ‘ - 𝐴 ) )  ∈  ℂ ) | 
						
							| 21 | 9 19 20 | sylancr | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( abs ‘ 𝐴 )  =  - 𝐴 )  →  ( i  ·  ( √ ‘ - 𝐴 ) )  ∈  ℂ ) | 
						
							| 22 |  | sqrtneglem | ⊢ ( ( - 𝐴  ∈  ℝ  ∧  0  ≤  - 𝐴 )  →  ( ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 )  =  - - 𝐴  ∧  0  ≤  ( ℜ ‘ ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∧  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∉  ℝ+ ) ) | 
						
							| 23 | 16 22 | syl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( abs ‘ 𝐴 )  =  - 𝐴 )  →  ( ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 )  =  - - 𝐴  ∧  0  ≤  ( ℜ ‘ ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∧  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∉  ℝ+ ) ) | 
						
							| 24 |  | negneg | ⊢ ( 𝐴  ∈  ℂ  →  - - 𝐴  =  𝐴 ) | 
						
							| 25 | 24 | adantr | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( abs ‘ 𝐴 )  =  - 𝐴 )  →  - - 𝐴  =  𝐴 ) | 
						
							| 26 | 25 | eqeq2d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( abs ‘ 𝐴 )  =  - 𝐴 )  →  ( ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 )  =  - - 𝐴  ↔  ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 )  =  𝐴 ) ) | 
						
							| 27 | 26 | 3anbi1d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( abs ‘ 𝐴 )  =  - 𝐴 )  →  ( ( ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 )  =  - - 𝐴  ∧  0  ≤  ( ℜ ‘ ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∧  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∉  ℝ+ )  ↔  ( ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∧  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∉  ℝ+ ) ) ) | 
						
							| 28 | 23 27 | mpbid | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( abs ‘ 𝐴 )  =  - 𝐴 )  →  ( ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∧  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∉  ℝ+ ) ) | 
						
							| 29 |  | oveq1 | ⊢ ( 𝑥  =  ( i  ·  ( √ ‘ - 𝐴 ) )  →  ( 𝑥 ↑ 2 )  =  ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 ) ) | 
						
							| 30 | 29 | eqeq1d | ⊢ ( 𝑥  =  ( i  ·  ( √ ‘ - 𝐴 ) )  →  ( ( 𝑥 ↑ 2 )  =  𝐴  ↔  ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 )  =  𝐴 ) ) | 
						
							| 31 |  | fveq2 | ⊢ ( 𝑥  =  ( i  ·  ( √ ‘ - 𝐴 ) )  →  ( ℜ ‘ 𝑥 )  =  ( ℜ ‘ ( i  ·  ( √ ‘ - 𝐴 ) ) ) ) | 
						
							| 32 | 31 | breq2d | ⊢ ( 𝑥  =  ( i  ·  ( √ ‘ - 𝐴 ) )  →  ( 0  ≤  ( ℜ ‘ 𝑥 )  ↔  0  ≤  ( ℜ ‘ ( i  ·  ( √ ‘ - 𝐴 ) ) ) ) ) | 
						
							| 33 |  | oveq2 | ⊢ ( 𝑥  =  ( i  ·  ( √ ‘ - 𝐴 ) )  →  ( i  ·  𝑥 )  =  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) ) ) | 
						
							| 34 |  | neleq1 | ⊢ ( ( i  ·  𝑥 )  =  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) )  →  ( ( i  ·  𝑥 )  ∉  ℝ+  ↔  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∉  ℝ+ ) ) | 
						
							| 35 | 33 34 | syl | ⊢ ( 𝑥  =  ( i  ·  ( √ ‘ - 𝐴 ) )  →  ( ( i  ·  𝑥 )  ∉  ℝ+  ↔  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∉  ℝ+ ) ) | 
						
							| 36 | 30 32 35 | 3anbi123d | ⊢ ( 𝑥  =  ( i  ·  ( √ ‘ - 𝐴 ) )  →  ( ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ )  ↔  ( ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∧  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∉  ℝ+ ) ) ) | 
						
							| 37 | 36 | rspcev | ⊢ ( ( ( i  ·  ( √ ‘ - 𝐴 ) )  ∈  ℂ  ∧  ( ( ( i  ·  ( √ ‘ - 𝐴 ) ) ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∧  ( i  ·  ( i  ·  ( √ ‘ - 𝐴 ) ) )  ∉  ℝ+ ) )  →  ∃ 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) | 
						
							| 38 | 21 28 37 | syl2anc | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( abs ‘ 𝐴 )  =  - 𝐴 )  →  ∃ 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) | 
						
							| 39 | 38 | ex | ⊢ ( 𝐴  ∈  ℂ  →  ( ( abs ‘ 𝐴 )  =  - 𝐴  →  ∃ 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) ) | 
						
							| 40 | 8 39 | sylbid | ⊢ ( 𝐴  ∈  ℂ  →  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  =  0  →  ∃ 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) ) | 
						
							| 41 |  | resqrtcl | ⊢ ( ( ( abs ‘ 𝐴 )  ∈  ℝ  ∧  0  ≤  ( abs ‘ 𝐴 ) )  →  ( √ ‘ ( abs ‘ 𝐴 ) )  ∈  ℝ ) | 
						
							| 42 | 1 10 41 | syl2anc | ⊢ ( 𝐴  ∈  ℂ  →  ( √ ‘ ( abs ‘ 𝐴 ) )  ∈  ℝ ) | 
						
							| 43 | 42 | recnd | ⊢ ( 𝐴  ∈  ℂ  →  ( √ ‘ ( abs ‘ 𝐴 ) )  ∈  ℂ ) | 
						
							| 44 | 43 | adantr | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( ( abs ‘ 𝐴 )  +  𝐴 )  ≠  0 )  →  ( √ ‘ ( abs ‘ 𝐴 ) )  ∈  ℂ ) | 
						
							| 45 |  | addcl | ⊢ ( ( ( abs ‘ 𝐴 )  ∈  ℂ  ∧  𝐴  ∈  ℂ )  →  ( ( abs ‘ 𝐴 )  +  𝐴 )  ∈  ℂ ) | 
						
							| 46 | 2 45 | mpancom | ⊢ ( 𝐴  ∈  ℂ  →  ( ( abs ‘ 𝐴 )  +  𝐴 )  ∈  ℂ ) | 
						
							| 47 | 46 | adantr | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( ( abs ‘ 𝐴 )  +  𝐴 )  ≠  0 )  →  ( ( abs ‘ 𝐴 )  +  𝐴 )  ∈  ℂ ) | 
						
							| 48 |  | abscl | ⊢ ( ( ( abs ‘ 𝐴 )  +  𝐴 )  ∈  ℂ  →  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) )  ∈  ℝ ) | 
						
							| 49 | 46 48 | syl | ⊢ ( 𝐴  ∈  ℂ  →  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) )  ∈  ℝ ) | 
						
							| 50 | 49 | recnd | ⊢ ( 𝐴  ∈  ℂ  →  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) )  ∈  ℂ ) | 
						
							| 51 | 50 | adantr | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( ( abs ‘ 𝐴 )  +  𝐴 )  ≠  0 )  →  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) )  ∈  ℂ ) | 
						
							| 52 | 46 | abs00ad | ⊢ ( 𝐴  ∈  ℂ  →  ( ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) )  =  0  ↔  ( ( abs ‘ 𝐴 )  +  𝐴 )  =  0 ) ) | 
						
							| 53 | 52 | necon3bid | ⊢ ( 𝐴  ∈  ℂ  →  ( ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) )  ≠  0  ↔  ( ( abs ‘ 𝐴 )  +  𝐴 )  ≠  0 ) ) | 
						
							| 54 | 53 | biimpar | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( ( abs ‘ 𝐴 )  +  𝐴 )  ≠  0 )  →  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) )  ≠  0 ) | 
						
							| 55 | 47 51 54 | divcld | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( ( abs ‘ 𝐴 )  +  𝐴 )  ≠  0 )  →  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) )  ∈  ℂ ) | 
						
							| 56 | 44 55 | mulcld | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( ( abs ‘ 𝐴 )  +  𝐴 )  ≠  0 )  →  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) )  ∈  ℂ ) | 
						
							| 57 |  | eqid | ⊢ ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) )  =  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) | 
						
							| 58 | 57 | sqreulem | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( ( abs ‘ 𝐴 )  +  𝐴 )  ≠  0 )  →  ( ( ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) )  ∧  ( i  ·  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) )  ∉  ℝ+ ) ) | 
						
							| 59 |  | oveq1 | ⊢ ( 𝑥  =  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) )  →  ( 𝑥 ↑ 2 )  =  ( ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) ↑ 2 ) ) | 
						
							| 60 | 59 | eqeq1d | ⊢ ( 𝑥  =  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) )  →  ( ( 𝑥 ↑ 2 )  =  𝐴  ↔  ( ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) ↑ 2 )  =  𝐴 ) ) | 
						
							| 61 |  | fveq2 | ⊢ ( 𝑥  =  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) )  →  ( ℜ ‘ 𝑥 )  =  ( ℜ ‘ ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) ) ) | 
						
							| 62 | 61 | breq2d | ⊢ ( 𝑥  =  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) )  →  ( 0  ≤  ( ℜ ‘ 𝑥 )  ↔  0  ≤  ( ℜ ‘ ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) ) ) ) | 
						
							| 63 |  | oveq2 | ⊢ ( 𝑥  =  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) )  →  ( i  ·  𝑥 )  =  ( i  ·  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) ) ) | 
						
							| 64 |  | neleq1 | ⊢ ( ( i  ·  𝑥 )  =  ( i  ·  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) )  →  ( ( i  ·  𝑥 )  ∉  ℝ+  ↔  ( i  ·  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) )  ∉  ℝ+ ) ) | 
						
							| 65 | 63 64 | syl | ⊢ ( 𝑥  =  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) )  →  ( ( i  ·  𝑥 )  ∉  ℝ+  ↔  ( i  ·  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) )  ∉  ℝ+ ) ) | 
						
							| 66 | 60 62 65 | 3anbi123d | ⊢ ( 𝑥  =  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) )  →  ( ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ )  ↔  ( ( ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) )  ∧  ( i  ·  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) )  ∉  ℝ+ ) ) ) | 
						
							| 67 | 66 | rspcev | ⊢ ( ( ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) )  ∈  ℂ  ∧  ( ( ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) )  ∧  ( i  ·  ( ( √ ‘ ( abs ‘ 𝐴 ) )  ·  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  /  ( abs ‘ ( ( abs ‘ 𝐴 )  +  𝐴 ) ) ) ) )  ∉  ℝ+ ) )  →  ∃ 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) | 
						
							| 68 | 56 58 67 | syl2anc | ⊢ ( ( 𝐴  ∈  ℂ  ∧  ( ( abs ‘ 𝐴 )  +  𝐴 )  ≠  0 )  →  ∃ 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) | 
						
							| 69 | 68 | ex | ⊢ ( 𝐴  ∈  ℂ  →  ( ( ( abs ‘ 𝐴 )  +  𝐴 )  ≠  0  →  ∃ 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) ) | 
						
							| 70 | 40 69 | pm2.61dne | ⊢ ( 𝐴  ∈  ℂ  →  ∃ 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) | 
						
							| 71 |  | sqrmo | ⊢ ( 𝐴  ∈  ℂ  →  ∃* 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) | 
						
							| 72 |  | reu5 | ⊢ ( ∃! 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ )  ↔  ( ∃ 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ )  ∧  ∃* 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) ) | 
						
							| 73 | 70 71 72 | sylanbrc | ⊢ ( 𝐴  ∈  ℂ  →  ∃! 𝑥  ∈  ℂ ( ( 𝑥 ↑ 2 )  =  𝐴  ∧  0  ≤  ( ℜ ‘ 𝑥 )  ∧  ( i  ·  𝑥 )  ∉  ℝ+ ) ) |