| Step | Hyp | Ref | Expression | 
						
							| 1 |  | quart.a |  |-  ( ph -> A e. CC ) | 
						
							| 2 |  | quart.b |  |-  ( ph -> B e. CC ) | 
						
							| 3 |  | quart.c |  |-  ( ph -> C e. CC ) | 
						
							| 4 |  | quart.d |  |-  ( ph -> D e. CC ) | 
						
							| 5 |  | quart.x |  |-  ( ph -> X e. CC ) | 
						
							| 6 |  | quart.e |  |-  ( ph -> E = -u ( A / 4 ) ) | 
						
							| 7 |  | quart.p |  |-  ( ph -> P = ( B - ( ( 3 / 8 ) x. ( A ^ 2 ) ) ) ) | 
						
							| 8 |  | quart.q |  |-  ( ph -> Q = ( ( C - ( ( A x. B ) / 2 ) ) + ( ( A ^ 3 ) / 8 ) ) ) | 
						
							| 9 |  | quart.r |  |-  ( ph -> R = ( ( D - ( ( C x. A ) / 4 ) ) + ( ( ( ( A ^ 2 ) x. B ) / ; 1 6 ) - ( ( 3 / ; ; 2 5 6 ) x. ( A ^ 4 ) ) ) ) ) | 
						
							| 10 |  | quart.u |  |-  ( ph -> U = ( ( P ^ 2 ) + ( ; 1 2 x. R ) ) ) | 
						
							| 11 |  | quart.v |  |-  ( ph -> V = ( ( -u ( 2 x. ( P ^ 3 ) ) - ( ; 2 7 x. ( Q ^ 2 ) ) ) + ( ; 7 2 x. ( P x. R ) ) ) ) | 
						
							| 12 |  | quart.w |  |-  ( ph -> W = ( sqrt ` ( ( V ^ 2 ) - ( 4 x. ( U ^ 3 ) ) ) ) ) | 
						
							| 13 |  | quart.s |  |-  ( ph -> S = ( ( sqrt ` M ) / 2 ) ) | 
						
							| 14 |  | quart.m |  |-  ( ph -> M = -u ( ( ( ( 2 x. P ) + T ) + ( U / T ) ) / 3 ) ) | 
						
							| 15 |  | quart.t |  |-  ( ph -> T = ( ( ( V + W ) / 2 ) ^c ( 1 / 3 ) ) ) | 
						
							| 16 |  | quart.t0 |  |-  ( ph -> T =/= 0 ) | 
						
							| 17 |  | quart.m0 |  |-  ( ph -> M =/= 0 ) | 
						
							| 18 |  | quart.i |  |-  ( ph -> I = ( sqrt ` ( ( -u ( S ^ 2 ) - ( P / 2 ) ) + ( ( Q / 4 ) / S ) ) ) ) | 
						
							| 19 |  | quart.j |  |-  ( ph -> J = ( sqrt ` ( ( -u ( S ^ 2 ) - ( P / 2 ) ) - ( ( Q / 4 ) / S ) ) ) ) | 
						
							| 20 | 6 | oveq2d |  |-  ( ph -> ( X - E ) = ( X - -u ( A / 4 ) ) ) | 
						
							| 21 |  | 4cn |  |-  4 e. CC | 
						
							| 22 | 21 | a1i |  |-  ( ph -> 4 e. CC ) | 
						
							| 23 |  | 4ne0 |  |-  4 =/= 0 | 
						
							| 24 | 23 | a1i |  |-  ( ph -> 4 =/= 0 ) | 
						
							| 25 | 1 22 24 | divcld |  |-  ( ph -> ( A / 4 ) e. CC ) | 
						
							| 26 | 5 25 | subnegd |  |-  ( ph -> ( X - -u ( A / 4 ) ) = ( X + ( A / 4 ) ) ) | 
						
							| 27 | 20 26 | eqtrd |  |-  ( ph -> ( X - E ) = ( X + ( A / 4 ) ) ) | 
						
							| 28 | 1 2 3 4 7 8 9 5 27 | quart1 |  |-  ( ph -> ( ( ( X ^ 4 ) + ( A x. ( X ^ 3 ) ) ) + ( ( B x. ( X ^ 2 ) ) + ( ( C x. X ) + D ) ) ) = ( ( ( ( X - E ) ^ 4 ) + ( P x. ( ( X - E ) ^ 2 ) ) ) + ( ( Q x. ( X - E ) ) + R ) ) ) | 
						
							| 29 | 28 | eqeq1d |  |-  ( ph -> ( ( ( ( X ^ 4 ) + ( A x. ( X ^ 3 ) ) ) + ( ( B x. ( X ^ 2 ) ) + ( ( C x. X ) + D ) ) ) = 0 <-> ( ( ( ( X - E ) ^ 4 ) + ( P x. ( ( X - E ) ^ 2 ) ) ) + ( ( Q x. ( X - E ) ) + R ) ) = 0 ) ) | 
						
							| 30 | 1 2 3 4 7 8 9 | quart1cl |  |-  ( ph -> ( P e. CC /\ Q e. CC /\ R e. CC ) ) | 
						
							| 31 | 30 | simp1d |  |-  ( ph -> P e. CC ) | 
						
							| 32 | 30 | simp2d |  |-  ( ph -> Q e. CC ) | 
						
							| 33 | 25 | negcld |  |-  ( ph -> -u ( A / 4 ) e. CC ) | 
						
							| 34 | 6 33 | eqeltrd |  |-  ( ph -> E e. CC ) | 
						
							| 35 | 5 34 | subcld |  |-  ( ph -> ( X - E ) e. CC ) | 
						
							| 36 | 1 2 3 4 1 6 7 8 9 10 11 12 13 14 15 16 | quartlem3 |  |-  ( ph -> ( S e. CC /\ M e. CC /\ T e. CC ) ) | 
						
							| 37 | 36 | simp1d |  |-  ( ph -> S e. CC ) | 
						
							| 38 | 13 | oveq2d |  |-  ( ph -> ( 2 x. S ) = ( 2 x. ( ( sqrt ` M ) / 2 ) ) ) | 
						
							| 39 | 36 | simp2d |  |-  ( ph -> M e. CC ) | 
						
							| 40 | 39 | sqrtcld |  |-  ( ph -> ( sqrt ` M ) e. CC ) | 
						
							| 41 |  | 2cnd |  |-  ( ph -> 2 e. CC ) | 
						
							| 42 |  | 2ne0 |  |-  2 =/= 0 | 
						
							| 43 | 42 | a1i |  |-  ( ph -> 2 =/= 0 ) | 
						
							| 44 | 40 41 43 | divcan2d |  |-  ( ph -> ( 2 x. ( ( sqrt ` M ) / 2 ) ) = ( sqrt ` M ) ) | 
						
							| 45 | 38 44 | eqtrd |  |-  ( ph -> ( 2 x. S ) = ( sqrt ` M ) ) | 
						
							| 46 | 45 | oveq1d |  |-  ( ph -> ( ( 2 x. S ) ^ 2 ) = ( ( sqrt ` M ) ^ 2 ) ) | 
						
							| 47 | 39 | sqsqrtd |  |-  ( ph -> ( ( sqrt ` M ) ^ 2 ) = M ) | 
						
							| 48 | 46 47 | eqtr2d |  |-  ( ph -> M = ( ( 2 x. S ) ^ 2 ) ) | 
						
							| 49 | 1 2 3 4 1 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | quartlem4 |  |-  ( ph -> ( S =/= 0 /\ I e. CC /\ J e. CC ) ) | 
						
							| 50 | 49 | simp2d |  |-  ( ph -> I e. CC ) | 
						
							| 51 | 18 | oveq1d |  |-  ( ph -> ( I ^ 2 ) = ( ( sqrt ` ( ( -u ( S ^ 2 ) - ( P / 2 ) ) + ( ( Q / 4 ) / S ) ) ) ^ 2 ) ) | 
						
							| 52 | 37 | sqcld |  |-  ( ph -> ( S ^ 2 ) e. CC ) | 
						
							| 53 | 52 | negcld |  |-  ( ph -> -u ( S ^ 2 ) e. CC ) | 
						
							| 54 | 31 | halfcld |  |-  ( ph -> ( P / 2 ) e. CC ) | 
						
							| 55 | 53 54 | subcld |  |-  ( ph -> ( -u ( S ^ 2 ) - ( P / 2 ) ) e. CC ) | 
						
							| 56 | 32 22 24 | divcld |  |-  ( ph -> ( Q / 4 ) e. CC ) | 
						
							| 57 | 49 | simp1d |  |-  ( ph -> S =/= 0 ) | 
						
							| 58 | 56 37 57 | divcld |  |-  ( ph -> ( ( Q / 4 ) / S ) e. CC ) | 
						
							| 59 | 55 58 | addcld |  |-  ( ph -> ( ( -u ( S ^ 2 ) - ( P / 2 ) ) + ( ( Q / 4 ) / S ) ) e. CC ) | 
						
							| 60 | 59 | sqsqrtd |  |-  ( ph -> ( ( sqrt ` ( ( -u ( S ^ 2 ) - ( P / 2 ) ) + ( ( Q / 4 ) / S ) ) ) ^ 2 ) = ( ( -u ( S ^ 2 ) - ( P / 2 ) ) + ( ( Q / 4 ) / S ) ) ) | 
						
							| 61 | 51 60 | eqtrd |  |-  ( ph -> ( I ^ 2 ) = ( ( -u ( S ^ 2 ) - ( P / 2 ) ) + ( ( Q / 4 ) / S ) ) ) | 
						
							| 62 | 30 | simp3d |  |-  ( ph -> R e. CC ) | 
						
							| 63 |  | 1cnd |  |-  ( ph -> 1 e. CC ) | 
						
							| 64 |  | 3z |  |-  3 e. ZZ | 
						
							| 65 |  | 1exp |  |-  ( 3 e. ZZ -> ( 1 ^ 3 ) = 1 ) | 
						
							| 66 | 64 65 | mp1i |  |-  ( ph -> ( 1 ^ 3 ) = 1 ) | 
						
							| 67 | 36 | simp3d |  |-  ( ph -> T e. CC ) | 
						
							| 68 | 67 | mullidd |  |-  ( ph -> ( 1 x. T ) = T ) | 
						
							| 69 | 68 | oveq2d |  |-  ( ph -> ( ( 2 x. P ) + ( 1 x. T ) ) = ( ( 2 x. P ) + T ) ) | 
						
							| 70 | 68 | oveq2d |  |-  ( ph -> ( U / ( 1 x. T ) ) = ( U / T ) ) | 
						
							| 71 | 69 70 | oveq12d |  |-  ( ph -> ( ( ( 2 x. P ) + ( 1 x. T ) ) + ( U / ( 1 x. T ) ) ) = ( ( ( 2 x. P ) + T ) + ( U / T ) ) ) | 
						
							| 72 | 71 | oveq1d |  |-  ( ph -> ( ( ( ( 2 x. P ) + ( 1 x. T ) ) + ( U / ( 1 x. T ) ) ) / 3 ) = ( ( ( ( 2 x. P ) + T ) + ( U / T ) ) / 3 ) ) | 
						
							| 73 | 72 | negeqd |  |-  ( ph -> -u ( ( ( ( 2 x. P ) + ( 1 x. T ) ) + ( U / ( 1 x. T ) ) ) / 3 ) = -u ( ( ( ( 2 x. P ) + T ) + ( U / T ) ) / 3 ) ) | 
						
							| 74 | 14 73 | eqtr4d |  |-  ( ph -> M = -u ( ( ( ( 2 x. P ) + ( 1 x. T ) ) + ( U / ( 1 x. T ) ) ) / 3 ) ) | 
						
							| 75 |  | oveq1 |  |-  ( x = 1 -> ( x ^ 3 ) = ( 1 ^ 3 ) ) | 
						
							| 76 | 75 | eqeq1d |  |-  ( x = 1 -> ( ( x ^ 3 ) = 1 <-> ( 1 ^ 3 ) = 1 ) ) | 
						
							| 77 |  | oveq1 |  |-  ( x = 1 -> ( x x. T ) = ( 1 x. T ) ) | 
						
							| 78 | 77 | oveq2d |  |-  ( x = 1 -> ( ( 2 x. P ) + ( x x. T ) ) = ( ( 2 x. P ) + ( 1 x. T ) ) ) | 
						
							| 79 | 77 | oveq2d |  |-  ( x = 1 -> ( U / ( x x. T ) ) = ( U / ( 1 x. T ) ) ) | 
						
							| 80 | 78 79 | oveq12d |  |-  ( x = 1 -> ( ( ( 2 x. P ) + ( x x. T ) ) + ( U / ( x x. T ) ) ) = ( ( ( 2 x. P ) + ( 1 x. T ) ) + ( U / ( 1 x. T ) ) ) ) | 
						
							| 81 | 80 | oveq1d |  |-  ( x = 1 -> ( ( ( ( 2 x. P ) + ( x x. T ) ) + ( U / ( x x. T ) ) ) / 3 ) = ( ( ( ( 2 x. P ) + ( 1 x. T ) ) + ( U / ( 1 x. T ) ) ) / 3 ) ) | 
						
							| 82 | 81 | negeqd |  |-  ( x = 1 -> -u ( ( ( ( 2 x. P ) + ( x x. T ) ) + ( U / ( x x. T ) ) ) / 3 ) = -u ( ( ( ( 2 x. P ) + ( 1 x. T ) ) + ( U / ( 1 x. T ) ) ) / 3 ) ) | 
						
							| 83 | 82 | eqeq2d |  |-  ( x = 1 -> ( M = -u ( ( ( ( 2 x. P ) + ( x x. T ) ) + ( U / ( x x. T ) ) ) / 3 ) <-> M = -u ( ( ( ( 2 x. P ) + ( 1 x. T ) ) + ( U / ( 1 x. T ) ) ) / 3 ) ) ) | 
						
							| 84 | 76 83 | anbi12d |  |-  ( x = 1 -> ( ( ( x ^ 3 ) = 1 /\ M = -u ( ( ( ( 2 x. P ) + ( x x. T ) ) + ( U / ( x x. T ) ) ) / 3 ) ) <-> ( ( 1 ^ 3 ) = 1 /\ M = -u ( ( ( ( 2 x. P ) + ( 1 x. T ) ) + ( U / ( 1 x. T ) ) ) / 3 ) ) ) ) | 
						
							| 85 | 84 | rspcev |  |-  ( ( 1 e. CC /\ ( ( 1 ^ 3 ) = 1 /\ M = -u ( ( ( ( 2 x. P ) + ( 1 x. T ) ) + ( U / ( 1 x. T ) ) ) / 3 ) ) ) -> E. x e. CC ( ( x ^ 3 ) = 1 /\ M = -u ( ( ( ( 2 x. P ) + ( x x. T ) ) + ( U / ( x x. T ) ) ) / 3 ) ) ) | 
						
							| 86 | 63 66 74 85 | syl12anc |  |-  ( ph -> E. x e. CC ( ( x ^ 3 ) = 1 /\ M = -u ( ( ( ( 2 x. P ) + ( x x. T ) ) + ( U / ( x x. T ) ) ) / 3 ) ) ) | 
						
							| 87 |  | 2cn |  |-  2 e. CC | 
						
							| 88 |  | mulcl |  |-  ( ( 2 e. CC /\ P e. CC ) -> ( 2 x. P ) e. CC ) | 
						
							| 89 | 87 31 88 | sylancr |  |-  ( ph -> ( 2 x. P ) e. CC ) | 
						
							| 90 | 31 | sqcld |  |-  ( ph -> ( P ^ 2 ) e. CC ) | 
						
							| 91 |  | mulcl |  |-  ( ( 4 e. CC /\ R e. CC ) -> ( 4 x. R ) e. CC ) | 
						
							| 92 | 21 62 91 | sylancr |  |-  ( ph -> ( 4 x. R ) e. CC ) | 
						
							| 93 | 90 92 | subcld |  |-  ( ph -> ( ( P ^ 2 ) - ( 4 x. R ) ) e. CC ) | 
						
							| 94 | 32 | sqcld |  |-  ( ph -> ( Q ^ 2 ) e. CC ) | 
						
							| 95 | 94 | negcld |  |-  ( ph -> -u ( Q ^ 2 ) e. CC ) | 
						
							| 96 | 15 | oveq1d |  |-  ( ph -> ( T ^ 3 ) = ( ( ( ( V + W ) / 2 ) ^c ( 1 / 3 ) ) ^ 3 ) ) | 
						
							| 97 | 1 2 3 4 1 6 7 8 9 10 11 12 | quartlem2 |  |-  ( ph -> ( U e. CC /\ V e. CC /\ W e. CC ) ) | 
						
							| 98 | 97 | simp2d |  |-  ( ph -> V e. CC ) | 
						
							| 99 | 97 | simp3d |  |-  ( ph -> W e. CC ) | 
						
							| 100 | 98 99 | addcld |  |-  ( ph -> ( V + W ) e. CC ) | 
						
							| 101 | 100 | halfcld |  |-  ( ph -> ( ( V + W ) / 2 ) e. CC ) | 
						
							| 102 |  | 3nn |  |-  3 e. NN | 
						
							| 103 |  | cxproot |  |-  ( ( ( ( V + W ) / 2 ) e. CC /\ 3 e. NN ) -> ( ( ( ( V + W ) / 2 ) ^c ( 1 / 3 ) ) ^ 3 ) = ( ( V + W ) / 2 ) ) | 
						
							| 104 | 101 102 103 | sylancl |  |-  ( ph -> ( ( ( ( V + W ) / 2 ) ^c ( 1 / 3 ) ) ^ 3 ) = ( ( V + W ) / 2 ) ) | 
						
							| 105 | 96 104 | eqtrd |  |-  ( ph -> ( T ^ 3 ) = ( ( V + W ) / 2 ) ) | 
						
							| 106 | 12 | oveq1d |  |-  ( ph -> ( W ^ 2 ) = ( ( sqrt ` ( ( V ^ 2 ) - ( 4 x. ( U ^ 3 ) ) ) ) ^ 2 ) ) | 
						
							| 107 | 98 | sqcld |  |-  ( ph -> ( V ^ 2 ) e. CC ) | 
						
							| 108 | 97 | simp1d |  |-  ( ph -> U e. CC ) | 
						
							| 109 |  | 3nn0 |  |-  3 e. NN0 | 
						
							| 110 |  | expcl |  |-  ( ( U e. CC /\ 3 e. NN0 ) -> ( U ^ 3 ) e. CC ) | 
						
							| 111 | 108 109 110 | sylancl |  |-  ( ph -> ( U ^ 3 ) e. CC ) | 
						
							| 112 |  | mulcl |  |-  ( ( 4 e. CC /\ ( U ^ 3 ) e. CC ) -> ( 4 x. ( U ^ 3 ) ) e. CC ) | 
						
							| 113 | 21 111 112 | sylancr |  |-  ( ph -> ( 4 x. ( U ^ 3 ) ) e. CC ) | 
						
							| 114 | 107 113 | subcld |  |-  ( ph -> ( ( V ^ 2 ) - ( 4 x. ( U ^ 3 ) ) ) e. CC ) | 
						
							| 115 | 114 | sqsqrtd |  |-  ( ph -> ( ( sqrt ` ( ( V ^ 2 ) - ( 4 x. ( U ^ 3 ) ) ) ) ^ 2 ) = ( ( V ^ 2 ) - ( 4 x. ( U ^ 3 ) ) ) ) | 
						
							| 116 | 106 115 | eqtrd |  |-  ( ph -> ( W ^ 2 ) = ( ( V ^ 2 ) - ( 4 x. ( U ^ 3 ) ) ) ) | 
						
							| 117 | 31 32 62 10 11 | quartlem1 |  |-  ( ph -> ( U = ( ( ( 2 x. P ) ^ 2 ) - ( 3 x. ( ( P ^ 2 ) - ( 4 x. R ) ) ) ) /\ V = ( ( ( 2 x. ( ( 2 x. P ) ^ 3 ) ) - ( 9 x. ( ( 2 x. P ) x. ( ( P ^ 2 ) - ( 4 x. R ) ) ) ) ) + ( ; 2 7 x. -u ( Q ^ 2 ) ) ) ) ) | 
						
							| 118 | 117 | simpld |  |-  ( ph -> U = ( ( ( 2 x. P ) ^ 2 ) - ( 3 x. ( ( P ^ 2 ) - ( 4 x. R ) ) ) ) ) | 
						
							| 119 | 117 | simprd |  |-  ( ph -> V = ( ( ( 2 x. ( ( 2 x. P ) ^ 3 ) ) - ( 9 x. ( ( 2 x. P ) x. ( ( P ^ 2 ) - ( 4 x. R ) ) ) ) ) + ( ; 2 7 x. -u ( Q ^ 2 ) ) ) ) | 
						
							| 120 | 89 93 95 39 67 105 99 116 118 119 16 | mcubic |  |-  ( ph -> ( ( ( ( M ^ 3 ) + ( ( 2 x. P ) x. ( M ^ 2 ) ) ) + ( ( ( ( P ^ 2 ) - ( 4 x. R ) ) x. M ) + -u ( Q ^ 2 ) ) ) = 0 <-> E. x e. CC ( ( x ^ 3 ) = 1 /\ M = -u ( ( ( ( 2 x. P ) + ( x x. T ) ) + ( U / ( x x. T ) ) ) / 3 ) ) ) ) | 
						
							| 121 | 86 120 | mpbird |  |-  ( ph -> ( ( ( M ^ 3 ) + ( ( 2 x. P ) x. ( M ^ 2 ) ) ) + ( ( ( ( P ^ 2 ) - ( 4 x. R ) ) x. M ) + -u ( Q ^ 2 ) ) ) = 0 ) | 
						
							| 122 | 49 | simp3d |  |-  ( ph -> J e. CC ) | 
						
							| 123 | 19 | oveq1d |  |-  ( ph -> ( J ^ 2 ) = ( ( sqrt ` ( ( -u ( S ^ 2 ) - ( P / 2 ) ) - ( ( Q / 4 ) / S ) ) ) ^ 2 ) ) | 
						
							| 124 | 55 58 | subcld |  |-  ( ph -> ( ( -u ( S ^ 2 ) - ( P / 2 ) ) - ( ( Q / 4 ) / S ) ) e. CC ) | 
						
							| 125 | 124 | sqsqrtd |  |-  ( ph -> ( ( sqrt ` ( ( -u ( S ^ 2 ) - ( P / 2 ) ) - ( ( Q / 4 ) / S ) ) ) ^ 2 ) = ( ( -u ( S ^ 2 ) - ( P / 2 ) ) - ( ( Q / 4 ) / S ) ) ) | 
						
							| 126 | 123 125 | eqtrd |  |-  ( ph -> ( J ^ 2 ) = ( ( -u ( S ^ 2 ) - ( P / 2 ) ) - ( ( Q / 4 ) / S ) ) ) | 
						
							| 127 | 31 32 35 37 48 17 50 61 62 121 122 126 | dquart |  |-  ( ph -> ( ( ( ( ( X - E ) ^ 4 ) + ( P x. ( ( X - E ) ^ 2 ) ) ) + ( ( Q x. ( X - E ) ) + R ) ) = 0 <-> ( ( ( X - E ) = ( -u S + I ) \/ ( X - E ) = ( -u S - I ) ) \/ ( ( X - E ) = ( S + J ) \/ ( X - E ) = ( S - J ) ) ) ) ) | 
						
							| 128 | 37 | negcld |  |-  ( ph -> -u S e. CC ) | 
						
							| 129 | 128 50 | addcld |  |-  ( ph -> ( -u S + I ) e. CC ) | 
						
							| 130 | 5 34 129 | subaddd |  |-  ( ph -> ( ( X - E ) = ( -u S + I ) <-> ( E + ( -u S + I ) ) = X ) ) | 
						
							| 131 | 34 37 | negsubd |  |-  ( ph -> ( E + -u S ) = ( E - S ) ) | 
						
							| 132 | 131 | oveq1d |  |-  ( ph -> ( ( E + -u S ) + I ) = ( ( E - S ) + I ) ) | 
						
							| 133 | 34 128 50 | addassd |  |-  ( ph -> ( ( E + -u S ) + I ) = ( E + ( -u S + I ) ) ) | 
						
							| 134 | 132 133 | eqtr3d |  |-  ( ph -> ( ( E - S ) + I ) = ( E + ( -u S + I ) ) ) | 
						
							| 135 | 134 | eqeq1d |  |-  ( ph -> ( ( ( E - S ) + I ) = X <-> ( E + ( -u S + I ) ) = X ) ) | 
						
							| 136 | 130 135 | bitr4d |  |-  ( ph -> ( ( X - E ) = ( -u S + I ) <-> ( ( E - S ) + I ) = X ) ) | 
						
							| 137 |  | eqcom |  |-  ( ( ( E - S ) + I ) = X <-> X = ( ( E - S ) + I ) ) | 
						
							| 138 | 136 137 | bitrdi |  |-  ( ph -> ( ( X - E ) = ( -u S + I ) <-> X = ( ( E - S ) + I ) ) ) | 
						
							| 139 | 128 50 | subcld |  |-  ( ph -> ( -u S - I ) e. CC ) | 
						
							| 140 | 5 34 139 | subaddd |  |-  ( ph -> ( ( X - E ) = ( -u S - I ) <-> ( E + ( -u S - I ) ) = X ) ) | 
						
							| 141 | 131 | oveq1d |  |-  ( ph -> ( ( E + -u S ) - I ) = ( ( E - S ) - I ) ) | 
						
							| 142 | 34 128 50 | addsubassd |  |-  ( ph -> ( ( E + -u S ) - I ) = ( E + ( -u S - I ) ) ) | 
						
							| 143 | 141 142 | eqtr3d |  |-  ( ph -> ( ( E - S ) - I ) = ( E + ( -u S - I ) ) ) | 
						
							| 144 | 143 | eqeq1d |  |-  ( ph -> ( ( ( E - S ) - I ) = X <-> ( E + ( -u S - I ) ) = X ) ) | 
						
							| 145 | 140 144 | bitr4d |  |-  ( ph -> ( ( X - E ) = ( -u S - I ) <-> ( ( E - S ) - I ) = X ) ) | 
						
							| 146 |  | eqcom |  |-  ( ( ( E - S ) - I ) = X <-> X = ( ( E - S ) - I ) ) | 
						
							| 147 | 145 146 | bitrdi |  |-  ( ph -> ( ( X - E ) = ( -u S - I ) <-> X = ( ( E - S ) - I ) ) ) | 
						
							| 148 | 138 147 | orbi12d |  |-  ( ph -> ( ( ( X - E ) = ( -u S + I ) \/ ( X - E ) = ( -u S - I ) ) <-> ( X = ( ( E - S ) + I ) \/ X = ( ( E - S ) - I ) ) ) ) | 
						
							| 149 | 37 122 | addcld |  |-  ( ph -> ( S + J ) e. CC ) | 
						
							| 150 | 5 34 149 | subaddd |  |-  ( ph -> ( ( X - E ) = ( S + J ) <-> ( E + ( S + J ) ) = X ) ) | 
						
							| 151 | 34 37 122 | addassd |  |-  ( ph -> ( ( E + S ) + J ) = ( E + ( S + J ) ) ) | 
						
							| 152 | 151 | eqeq1d |  |-  ( ph -> ( ( ( E + S ) + J ) = X <-> ( E + ( S + J ) ) = X ) ) | 
						
							| 153 | 150 152 | bitr4d |  |-  ( ph -> ( ( X - E ) = ( S + J ) <-> ( ( E + S ) + J ) = X ) ) | 
						
							| 154 |  | eqcom |  |-  ( ( ( E + S ) + J ) = X <-> X = ( ( E + S ) + J ) ) | 
						
							| 155 | 153 154 | bitrdi |  |-  ( ph -> ( ( X - E ) = ( S + J ) <-> X = ( ( E + S ) + J ) ) ) | 
						
							| 156 | 37 122 | subcld |  |-  ( ph -> ( S - J ) e. CC ) | 
						
							| 157 | 5 34 156 | subaddd |  |-  ( ph -> ( ( X - E ) = ( S - J ) <-> ( E + ( S - J ) ) = X ) ) | 
						
							| 158 | 34 37 122 | addsubassd |  |-  ( ph -> ( ( E + S ) - J ) = ( E + ( S - J ) ) ) | 
						
							| 159 | 158 | eqeq1d |  |-  ( ph -> ( ( ( E + S ) - J ) = X <-> ( E + ( S - J ) ) = X ) ) | 
						
							| 160 | 157 159 | bitr4d |  |-  ( ph -> ( ( X - E ) = ( S - J ) <-> ( ( E + S ) - J ) = X ) ) | 
						
							| 161 |  | eqcom |  |-  ( ( ( E + S ) - J ) = X <-> X = ( ( E + S ) - J ) ) | 
						
							| 162 | 160 161 | bitrdi |  |-  ( ph -> ( ( X - E ) = ( S - J ) <-> X = ( ( E + S ) - J ) ) ) | 
						
							| 163 | 155 162 | orbi12d |  |-  ( ph -> ( ( ( X - E ) = ( S + J ) \/ ( X - E ) = ( S - J ) ) <-> ( X = ( ( E + S ) + J ) \/ X = ( ( E + S ) - J ) ) ) ) | 
						
							| 164 | 148 163 | orbi12d |  |-  ( ph -> ( ( ( ( X - E ) = ( -u S + I ) \/ ( X - E ) = ( -u S - I ) ) \/ ( ( X - E ) = ( S + J ) \/ ( X - E ) = ( S - J ) ) ) <-> ( ( X = ( ( E - S ) + I ) \/ X = ( ( E - S ) - I ) ) \/ ( X = ( ( E + S ) + J ) \/ X = ( ( E + S ) - J ) ) ) ) ) | 
						
							| 165 | 29 127 164 | 3bitrd |  |-  ( ph -> ( ( ( ( X ^ 4 ) + ( A x. ( X ^ 3 ) ) ) + ( ( B x. ( X ^ 2 ) ) + ( ( C x. X ) + D ) ) ) = 0 <-> ( ( X = ( ( E - S ) + I ) \/ X = ( ( E - S ) - I ) ) \/ ( X = ( ( E + S ) + J ) \/ X = ( ( E + S ) - J ) ) ) ) ) |