| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							quart1.a | 
							 |-  ( ph -> A e. CC )  | 
						
						
							| 2 | 
							
								
							 | 
							quart1.b | 
							 |-  ( ph -> B e. CC )  | 
						
						
							| 3 | 
							
								
							 | 
							quart1.c | 
							 |-  ( ph -> C e. CC )  | 
						
						
							| 4 | 
							
								
							 | 
							quart1.d | 
							 |-  ( ph -> D e. CC )  | 
						
						
							| 5 | 
							
								
							 | 
							quart1.p | 
							 |-  ( ph -> P = ( B - ( ( 3 / 8 ) x. ( A ^ 2 ) ) ) )  | 
						
						
							| 6 | 
							
								
							 | 
							quart1.q | 
							 |-  ( ph -> Q = ( ( C - ( ( A x. B ) / 2 ) ) + ( ( A ^ 3 ) / 8 ) ) )  | 
						
						
							| 7 | 
							
								
							 | 
							quart1.r | 
							 |-  ( ph -> R = ( ( D - ( ( C x. A ) / 4 ) ) + ( ( ( ( A ^ 2 ) x. B ) / ; 1 6 ) - ( ( 3 / ; ; 2 5 6 ) x. ( A ^ 4 ) ) ) ) )  | 
						
						
							| 8 | 
							
								
							 | 
							3cn | 
							 |-  3 e. CC  | 
						
						
							| 9 | 
							
								
							 | 
							8cn | 
							 |-  8 e. CC  | 
						
						
							| 10 | 
							
								
							 | 
							8nn | 
							 |-  8 e. NN  | 
						
						
							| 11 | 
							
								10
							 | 
							nnne0i | 
							 |-  8 =/= 0  | 
						
						
							| 12 | 
							
								8 9 11
							 | 
							divcli | 
							 |-  ( 3 / 8 ) e. CC  | 
						
						
							| 13 | 
							
								1
							 | 
							sqcld | 
							 |-  ( ph -> ( A ^ 2 ) e. CC )  | 
						
						
							| 14 | 
							
								
							 | 
							mulcl | 
							 |-  ( ( ( 3 / 8 ) e. CC /\ ( A ^ 2 ) e. CC ) -> ( ( 3 / 8 ) x. ( A ^ 2 ) ) e. CC )  | 
						
						
							| 15 | 
							
								12 13 14
							 | 
							sylancr | 
							 |-  ( ph -> ( ( 3 / 8 ) x. ( A ^ 2 ) ) e. CC )  | 
						
						
							| 16 | 
							
								2 15
							 | 
							subcld | 
							 |-  ( ph -> ( B - ( ( 3 / 8 ) x. ( A ^ 2 ) ) ) e. CC )  | 
						
						
							| 17 | 
							
								5 16
							 | 
							eqeltrd | 
							 |-  ( ph -> P e. CC )  | 
						
						
							| 18 | 
							
								1 2
							 | 
							mulcld | 
							 |-  ( ph -> ( A x. B ) e. CC )  | 
						
						
							| 19 | 
							
								18
							 | 
							halfcld | 
							 |-  ( ph -> ( ( A x. B ) / 2 ) e. CC )  | 
						
						
							| 20 | 
							
								3 19
							 | 
							subcld | 
							 |-  ( ph -> ( C - ( ( A x. B ) / 2 ) ) e. CC )  | 
						
						
							| 21 | 
							
								
							 | 
							3nn0 | 
							 |-  3 e. NN0  | 
						
						
							| 22 | 
							
								
							 | 
							expcl | 
							 |-  ( ( A e. CC /\ 3 e. NN0 ) -> ( A ^ 3 ) e. CC )  | 
						
						
							| 23 | 
							
								1 21 22
							 | 
							sylancl | 
							 |-  ( ph -> ( A ^ 3 ) e. CC )  | 
						
						
							| 24 | 
							
								9
							 | 
							a1i | 
							 |-  ( ph -> 8 e. CC )  | 
						
						
							| 25 | 
							
								11
							 | 
							a1i | 
							 |-  ( ph -> 8 =/= 0 )  | 
						
						
							| 26 | 
							
								23 24 25
							 | 
							divcld | 
							 |-  ( ph -> ( ( A ^ 3 ) / 8 ) e. CC )  | 
						
						
							| 27 | 
							
								20 26
							 | 
							addcld | 
							 |-  ( ph -> ( ( C - ( ( A x. B ) / 2 ) ) + ( ( A ^ 3 ) / 8 ) ) e. CC )  | 
						
						
							| 28 | 
							
								6 27
							 | 
							eqeltrd | 
							 |-  ( ph -> Q e. CC )  | 
						
						
							| 29 | 
							
								3 1
							 | 
							mulcld | 
							 |-  ( ph -> ( C x. A ) e. CC )  | 
						
						
							| 30 | 
							
								
							 | 
							4cn | 
							 |-  4 e. CC  | 
						
						
							| 31 | 
							
								30
							 | 
							a1i | 
							 |-  ( ph -> 4 e. CC )  | 
						
						
							| 32 | 
							
								
							 | 
							4ne0 | 
							 |-  4 =/= 0  | 
						
						
							| 33 | 
							
								32
							 | 
							a1i | 
							 |-  ( ph -> 4 =/= 0 )  | 
						
						
							| 34 | 
							
								29 31 33
							 | 
							divcld | 
							 |-  ( ph -> ( ( C x. A ) / 4 ) e. CC )  | 
						
						
							| 35 | 
							
								4 34
							 | 
							subcld | 
							 |-  ( ph -> ( D - ( ( C x. A ) / 4 ) ) e. CC )  | 
						
						
							| 36 | 
							
								13 2
							 | 
							mulcld | 
							 |-  ( ph -> ( ( A ^ 2 ) x. B ) e. CC )  | 
						
						
							| 37 | 
							
								
							 | 
							1nn0 | 
							 |-  1 e. NN0  | 
						
						
							| 38 | 
							
								
							 | 
							6nn | 
							 |-  6 e. NN  | 
						
						
							| 39 | 
							
								37 38
							 | 
							decnncl | 
							 |-  ; 1 6 e. NN  | 
						
						
							| 40 | 
							
								39
							 | 
							nncni | 
							 |-  ; 1 6 e. CC  | 
						
						
							| 41 | 
							
								40
							 | 
							a1i | 
							 |-  ( ph -> ; 1 6 e. CC )  | 
						
						
							| 42 | 
							
								39
							 | 
							nnne0i | 
							 |-  ; 1 6 =/= 0  | 
						
						
							| 43 | 
							
								42
							 | 
							a1i | 
							 |-  ( ph -> ; 1 6 =/= 0 )  | 
						
						
							| 44 | 
							
								36 41 43
							 | 
							divcld | 
							 |-  ( ph -> ( ( ( A ^ 2 ) x. B ) / ; 1 6 ) e. CC )  | 
						
						
							| 45 | 
							
								
							 | 
							2nn0 | 
							 |-  2 e. NN0  | 
						
						
							| 46 | 
							
								
							 | 
							5nn0 | 
							 |-  5 e. NN0  | 
						
						
							| 47 | 
							
								45 46
							 | 
							deccl | 
							 |-  ; 2 5 e. NN0  | 
						
						
							| 48 | 
							
								47 38
							 | 
							decnncl | 
							 |-  ; ; 2 5 6 e. NN  | 
						
						
							| 49 | 
							
								48
							 | 
							nncni | 
							 |-  ; ; 2 5 6 e. CC  | 
						
						
							| 50 | 
							
								48
							 | 
							nnne0i | 
							 |-  ; ; 2 5 6 =/= 0  | 
						
						
							| 51 | 
							
								8 49 50
							 | 
							divcli | 
							 |-  ( 3 / ; ; 2 5 6 ) e. CC  | 
						
						
							| 52 | 
							
								
							 | 
							4nn0 | 
							 |-  4 e. NN0  | 
						
						
							| 53 | 
							
								
							 | 
							expcl | 
							 |-  ( ( A e. CC /\ 4 e. NN0 ) -> ( A ^ 4 ) e. CC )  | 
						
						
							| 54 | 
							
								1 52 53
							 | 
							sylancl | 
							 |-  ( ph -> ( A ^ 4 ) e. CC )  | 
						
						
							| 55 | 
							
								
							 | 
							mulcl | 
							 |-  ( ( ( 3 / ; ; 2 5 6 ) e. CC /\ ( A ^ 4 ) e. CC ) -> ( ( 3 / ; ; 2 5 6 ) x. ( A ^ 4 ) ) e. CC )  | 
						
						
							| 56 | 
							
								51 54 55
							 | 
							sylancr | 
							 |-  ( ph -> ( ( 3 / ; ; 2 5 6 ) x. ( A ^ 4 ) ) e. CC )  | 
						
						
							| 57 | 
							
								44 56
							 | 
							subcld | 
							 |-  ( ph -> ( ( ( ( A ^ 2 ) x. B ) / ; 1 6 ) - ( ( 3 / ; ; 2 5 6 ) x. ( A ^ 4 ) ) ) e. CC )  | 
						
						
							| 58 | 
							
								35 57
							 | 
							addcld | 
							 |-  ( ph -> ( ( D - ( ( C x. A ) / 4 ) ) + ( ( ( ( A ^ 2 ) x. B ) / ; 1 6 ) - ( ( 3 / ; ; 2 5 6 ) x. ( A ^ 4 ) ) ) ) e. CC )  | 
						
						
							| 59 | 
							
								7 58
							 | 
							eqeltrd | 
							 |-  ( ph -> R e. CC )  | 
						
						
							| 60 | 
							
								17 28 59
							 | 
							3jca | 
							 |-  ( ph -> ( P e. CC /\ Q e. CC /\ R e. CC ) )  |