| 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 ) ) |