| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							quart.a | 
							⊢ ( 𝜑  →  𝐴  ∈  ℂ )  | 
						
						
							| 2 | 
							
								
							 | 
							quart.b | 
							⊢ ( 𝜑  →  𝐵  ∈  ℂ )  | 
						
						
							| 3 | 
							
								
							 | 
							quart.c | 
							⊢ ( 𝜑  →  𝐶  ∈  ℂ )  | 
						
						
							| 4 | 
							
								
							 | 
							quart.d | 
							⊢ ( 𝜑  →  𝐷  ∈  ℂ )  | 
						
						
							| 5 | 
							
								
							 | 
							quart.x | 
							⊢ ( 𝜑  →  𝑋  ∈  ℂ )  | 
						
						
							| 6 | 
							
								
							 | 
							quart.e | 
							⊢ ( 𝜑  →  𝐸  =  - ( 𝐴  /  4 ) )  | 
						
						
							| 7 | 
							
								
							 | 
							quart.p | 
							⊢ ( 𝜑  →  𝑃  =  ( 𝐵  −  ( ( 3  /  8 )  ·  ( 𝐴 ↑ 2 ) ) ) )  | 
						
						
							| 8 | 
							
								
							 | 
							quart.q | 
							⊢ ( 𝜑  →  𝑄  =  ( ( 𝐶  −  ( ( 𝐴  ·  𝐵 )  /  2 ) )  +  ( ( 𝐴 ↑ 3 )  /  8 ) ) )  | 
						
						
							| 9 | 
							
								
							 | 
							quart.r | 
							⊢ ( 𝜑  →  𝑅  =  ( ( 𝐷  −  ( ( 𝐶  ·  𝐴 )  /  4 ) )  +  ( ( ( ( 𝐴 ↑ 2 )  ·  𝐵 )  /  ; 1 6 )  −  ( ( 3  /  ; ; 2 5 6 )  ·  ( 𝐴 ↑ 4 ) ) ) ) )  | 
						
						
							| 10 | 
							
								
							 | 
							quart.u | 
							⊢ ( 𝜑  →  𝑈  =  ( ( 𝑃 ↑ 2 )  +  ( ; 1 2  ·  𝑅 ) ) )  | 
						
						
							| 11 | 
							
								
							 | 
							quart.v | 
							⊢ ( 𝜑  →  𝑉  =  ( ( - ( 2  ·  ( 𝑃 ↑ 3 ) )  −  ( ; 2 7  ·  ( 𝑄 ↑ 2 ) ) )  +  ( ; 7 2  ·  ( 𝑃  ·  𝑅 ) ) ) )  | 
						
						
							| 12 | 
							
								
							 | 
							quart.w | 
							⊢ ( 𝜑  →  𝑊  =  ( √ ‘ ( ( 𝑉 ↑ 2 )  −  ( 4  ·  ( 𝑈 ↑ 3 ) ) ) ) )  | 
						
						
							| 13 | 
							
								
							 | 
							quart.s | 
							⊢ ( 𝜑  →  𝑆  =  ( ( √ ‘ 𝑀 )  /  2 ) )  | 
						
						
							| 14 | 
							
								
							 | 
							quart.m | 
							⊢ ( 𝜑  →  𝑀  =  - ( ( ( ( 2  ·  𝑃 )  +  𝑇 )  +  ( 𝑈  /  𝑇 ) )  /  3 ) )  | 
						
						
							| 15 | 
							
								
							 | 
							quart.t | 
							⊢ ( 𝜑  →  𝑇  =  ( ( ( 𝑉  +  𝑊 )  /  2 ) ↑𝑐 ( 1  /  3 ) ) )  | 
						
						
							| 16 | 
							
								
							 | 
							quart.t0 | 
							⊢ ( 𝜑  →  𝑇  ≠  0 )  | 
						
						
							| 17 | 
							
								
							 | 
							2cn | 
							⊢ 2  ∈  ℂ  | 
						
						
							| 18 | 
							
								1 2 3 4 7 8 9
							 | 
							quart1cl | 
							⊢ ( 𝜑  →  ( 𝑃  ∈  ℂ  ∧  𝑄  ∈  ℂ  ∧  𝑅  ∈  ℂ ) )  | 
						
						
							| 19 | 
							
								18
							 | 
							simp1d | 
							⊢ ( 𝜑  →  𝑃  ∈  ℂ )  | 
						
						
							| 20 | 
							
								
							 | 
							mulcl | 
							⊢ ( ( 2  ∈  ℂ  ∧  𝑃  ∈  ℂ )  →  ( 2  ·  𝑃 )  ∈  ℂ )  | 
						
						
							| 21 | 
							
								17 19 20
							 | 
							sylancr | 
							⊢ ( 𝜑  →  ( 2  ·  𝑃 )  ∈  ℂ )  | 
						
						
							| 22 | 
							
								1 2 3 4 1 6 7 8 9 10 11 12
							 | 
							quartlem2 | 
							⊢ ( 𝜑  →  ( 𝑈  ∈  ℂ  ∧  𝑉  ∈  ℂ  ∧  𝑊  ∈  ℂ ) )  | 
						
						
							| 23 | 
							
								22
							 | 
							simp2d | 
							⊢ ( 𝜑  →  𝑉  ∈  ℂ )  | 
						
						
							| 24 | 
							
								22
							 | 
							simp3d | 
							⊢ ( 𝜑  →  𝑊  ∈  ℂ )  | 
						
						
							| 25 | 
							
								23 24
							 | 
							addcld | 
							⊢ ( 𝜑  →  ( 𝑉  +  𝑊 )  ∈  ℂ )  | 
						
						
							| 26 | 
							
								25
							 | 
							halfcld | 
							⊢ ( 𝜑  →  ( ( 𝑉  +  𝑊 )  /  2 )  ∈  ℂ )  | 
						
						
							| 27 | 
							
								
							 | 
							3nn | 
							⊢ 3  ∈  ℕ  | 
						
						
							| 28 | 
							
								
							 | 
							nnrecre | 
							⊢ ( 3  ∈  ℕ  →  ( 1  /  3 )  ∈  ℝ )  | 
						
						
							| 29 | 
							
								27 28
							 | 
							ax-mp | 
							⊢ ( 1  /  3 )  ∈  ℝ  | 
						
						
							| 30 | 
							
								29
							 | 
							recni | 
							⊢ ( 1  /  3 )  ∈  ℂ  | 
						
						
							| 31 | 
							
								
							 | 
							cxpcl | 
							⊢ ( ( ( ( 𝑉  +  𝑊 )  /  2 )  ∈  ℂ  ∧  ( 1  /  3 )  ∈  ℂ )  →  ( ( ( 𝑉  +  𝑊 )  /  2 ) ↑𝑐 ( 1  /  3 ) )  ∈  ℂ )  | 
						
						
							| 32 | 
							
								26 30 31
							 | 
							sylancl | 
							⊢ ( 𝜑  →  ( ( ( 𝑉  +  𝑊 )  /  2 ) ↑𝑐 ( 1  /  3 ) )  ∈  ℂ )  | 
						
						
							| 33 | 
							
								15 32
							 | 
							eqeltrd | 
							⊢ ( 𝜑  →  𝑇  ∈  ℂ )  | 
						
						
							| 34 | 
							
								21 33
							 | 
							addcld | 
							⊢ ( 𝜑  →  ( ( 2  ·  𝑃 )  +  𝑇 )  ∈  ℂ )  | 
						
						
							| 35 | 
							
								22
							 | 
							simp1d | 
							⊢ ( 𝜑  →  𝑈  ∈  ℂ )  | 
						
						
							| 36 | 
							
								35 33 16
							 | 
							divcld | 
							⊢ ( 𝜑  →  ( 𝑈  /  𝑇 )  ∈  ℂ )  | 
						
						
							| 37 | 
							
								34 36
							 | 
							addcld | 
							⊢ ( 𝜑  →  ( ( ( 2  ·  𝑃 )  +  𝑇 )  +  ( 𝑈  /  𝑇 ) )  ∈  ℂ )  | 
						
						
							| 38 | 
							
								
							 | 
							3cn | 
							⊢ 3  ∈  ℂ  | 
						
						
							| 39 | 
							
								38
							 | 
							a1i | 
							⊢ ( 𝜑  →  3  ∈  ℂ )  | 
						
						
							| 40 | 
							
								
							 | 
							3ne0 | 
							⊢ 3  ≠  0  | 
						
						
							| 41 | 
							
								40
							 | 
							a1i | 
							⊢ ( 𝜑  →  3  ≠  0 )  | 
						
						
							| 42 | 
							
								37 39 41
							 | 
							divcld | 
							⊢ ( 𝜑  →  ( ( ( ( 2  ·  𝑃 )  +  𝑇 )  +  ( 𝑈  /  𝑇 ) )  /  3 )  ∈  ℂ )  | 
						
						
							| 43 | 
							
								42
							 | 
							negcld | 
							⊢ ( 𝜑  →  - ( ( ( ( 2  ·  𝑃 )  +  𝑇 )  +  ( 𝑈  /  𝑇 ) )  /  3 )  ∈  ℂ )  | 
						
						
							| 44 | 
							
								14 43
							 | 
							eqeltrd | 
							⊢ ( 𝜑  →  𝑀  ∈  ℂ )  | 
						
						
							| 45 | 
							
								44
							 | 
							sqrtcld | 
							⊢ ( 𝜑  →  ( √ ‘ 𝑀 )  ∈  ℂ )  | 
						
						
							| 46 | 
							
								45
							 | 
							halfcld | 
							⊢ ( 𝜑  →  ( ( √ ‘ 𝑀 )  /  2 )  ∈  ℂ )  | 
						
						
							| 47 | 
							
								13 46
							 | 
							eqeltrd | 
							⊢ ( 𝜑  →  𝑆  ∈  ℂ )  | 
						
						
							| 48 | 
							
								47 44 33
							 | 
							3jca | 
							⊢ ( 𝜑  →  ( 𝑆  ∈  ℂ  ∧  𝑀  ∈  ℂ  ∧  𝑇  ∈  ℂ ) )  |