| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ip1i.1 |  |-  X = ( BaseSet ` U ) | 
						
							| 2 |  | ip1i.2 |  |-  G = ( +v ` U ) | 
						
							| 3 |  | ip1i.4 |  |-  S = ( .sOLD ` U ) | 
						
							| 4 |  | ip1i.7 |  |-  P = ( .iOLD ` U ) | 
						
							| 5 |  | ip1i.9 |  |-  U e. CPreHilOLD | 
						
							| 6 |  | ip1i.a |  |-  A e. X | 
						
							| 7 |  | ip1i.b |  |-  B e. X | 
						
							| 8 |  | ip1i.c |  |-  C e. X | 
						
							| 9 |  | ip1i.6 |  |-  N = ( normCV ` U ) | 
						
							| 10 |  | ip0i.j |  |-  J e. CC | 
						
							| 11 | 5 | phnvi |  |-  U e. NrmCVec | 
						
							| 12 | 1 2 3 9 4 | 4ipval2 |  |-  ( ( U e. NrmCVec /\ A e. X /\ C e. X ) -> ( 4 x. ( A P C ) ) = ( ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) | 
						
							| 13 | 11 6 8 12 | mp3an |  |-  ( 4 x. ( A P C ) ) = ( ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) | 
						
							| 14 | 13 | oveq2i |  |-  ( 2 x. ( 4 x. ( A P C ) ) ) = ( 2 x. ( ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) | 
						
							| 15 |  | 2cn |  |-  2 e. CC | 
						
							| 16 |  | 4cn |  |-  4 e. CC | 
						
							| 17 | 1 4 | dipcl |  |-  ( ( U e. NrmCVec /\ A e. X /\ C e. X ) -> ( A P C ) e. CC ) | 
						
							| 18 | 11 6 8 17 | mp3an |  |-  ( A P C ) e. CC | 
						
							| 19 | 15 16 18 | mul12i |  |-  ( 2 x. ( 4 x. ( A P C ) ) ) = ( 4 x. ( 2 x. ( A P C ) ) ) | 
						
							| 20 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ A e. X /\ C e. X ) -> ( A G C ) e. X ) | 
						
							| 21 | 11 6 8 20 | mp3an |  |-  ( A G C ) e. X | 
						
							| 22 | 1 9 11 21 | nvcli |  |-  ( N ` ( A G C ) ) e. RR | 
						
							| 23 | 22 | resqcli |  |-  ( ( N ` ( A G C ) ) ^ 2 ) e. RR | 
						
							| 24 | 23 | recni |  |-  ( ( N ` ( A G C ) ) ^ 2 ) e. CC | 
						
							| 25 |  | ax-1cn |  |-  1 e. CC | 
						
							| 26 | 25 | negcli |  |-  -u 1 e. CC | 
						
							| 27 | 1 3 | nvscl |  |-  ( ( U e. NrmCVec /\ -u 1 e. CC /\ C e. X ) -> ( -u 1 S C ) e. X ) | 
						
							| 28 | 11 26 8 27 | mp3an |  |-  ( -u 1 S C ) e. X | 
						
							| 29 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ A e. X /\ ( -u 1 S C ) e. X ) -> ( A G ( -u 1 S C ) ) e. X ) | 
						
							| 30 | 11 6 28 29 | mp3an |  |-  ( A G ( -u 1 S C ) ) e. X | 
						
							| 31 | 1 9 11 30 | nvcli |  |-  ( N ` ( A G ( -u 1 S C ) ) ) e. RR | 
						
							| 32 | 31 | resqcli |  |-  ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) e. RR | 
						
							| 33 | 32 | recni |  |-  ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) e. CC | 
						
							| 34 | 24 33 | subcli |  |-  ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) e. CC | 
						
							| 35 |  | ax-icn |  |-  _i e. CC | 
						
							| 36 | 1 3 | nvscl |  |-  ( ( U e. NrmCVec /\ _i e. CC /\ C e. X ) -> ( _i S C ) e. X ) | 
						
							| 37 | 11 35 8 36 | mp3an |  |-  ( _i S C ) e. X | 
						
							| 38 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ A e. X /\ ( _i S C ) e. X ) -> ( A G ( _i S C ) ) e. X ) | 
						
							| 39 | 11 6 37 38 | mp3an |  |-  ( A G ( _i S C ) ) e. X | 
						
							| 40 | 1 9 11 39 | nvcli |  |-  ( N ` ( A G ( _i S C ) ) ) e. RR | 
						
							| 41 | 40 | resqcli |  |-  ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) e. RR | 
						
							| 42 | 41 | recni |  |-  ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) e. CC | 
						
							| 43 | 35 | negcli |  |-  -u _i e. CC | 
						
							| 44 | 1 3 | nvscl |  |-  ( ( U e. NrmCVec /\ -u _i e. CC /\ C e. X ) -> ( -u _i S C ) e. X ) | 
						
							| 45 | 11 43 8 44 | mp3an |  |-  ( -u _i S C ) e. X | 
						
							| 46 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ A e. X /\ ( -u _i S C ) e. X ) -> ( A G ( -u _i S C ) ) e. X ) | 
						
							| 47 | 11 6 45 46 | mp3an |  |-  ( A G ( -u _i S C ) ) e. X | 
						
							| 48 | 1 9 11 47 | nvcli |  |-  ( N ` ( A G ( -u _i S C ) ) ) e. RR | 
						
							| 49 | 48 | resqcli |  |-  ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) e. RR | 
						
							| 50 | 49 | recni |  |-  ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) e. CC | 
						
							| 51 | 42 50 | subcli |  |-  ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) e. CC | 
						
							| 52 | 35 51 | mulcli |  |-  ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) e. CC | 
						
							| 53 | 15 34 52 | adddii |  |-  ( 2 x. ( ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) = ( ( 2 x. ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) ) + ( 2 x. ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) | 
						
							| 54 | 1 2 3 4 5 6 7 8 9 25 | ip0i |  |-  ( ( ( ( N ` ( ( A G B ) G ( 1 S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( 1 S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) ) = ( 2 x. ( ( ( N ` ( A G ( 1 S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) ) | 
						
							| 55 | 1 3 | nvsid |  |-  ( ( U e. NrmCVec /\ C e. X ) -> ( 1 S C ) = C ) | 
						
							| 56 | 11 8 55 | mp2an |  |-  ( 1 S C ) = C | 
						
							| 57 | 56 | oveq2i |  |-  ( ( A G B ) G ( 1 S C ) ) = ( ( A G B ) G C ) | 
						
							| 58 | 57 | fveq2i |  |-  ( N ` ( ( A G B ) G ( 1 S C ) ) ) = ( N ` ( ( A G B ) G C ) ) | 
						
							| 59 | 58 | oveq1i |  |-  ( ( N ` ( ( A G B ) G ( 1 S C ) ) ) ^ 2 ) = ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) | 
						
							| 60 | 59 | oveq1i |  |-  ( ( ( N ` ( ( A G B ) G ( 1 S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) = ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) | 
						
							| 61 | 56 | oveq2i |  |-  ( ( A G ( -u 1 S B ) ) G ( 1 S C ) ) = ( ( A G ( -u 1 S B ) ) G C ) | 
						
							| 62 | 61 | fveq2i |  |-  ( N ` ( ( A G ( -u 1 S B ) ) G ( 1 S C ) ) ) = ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) | 
						
							| 63 | 62 | oveq1i |  |-  ( ( N ` ( ( A G ( -u 1 S B ) ) G ( 1 S C ) ) ) ^ 2 ) = ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) | 
						
							| 64 | 63 | oveq1i |  |-  ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( 1 S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) = ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) | 
						
							| 65 | 60 64 | oveq12i |  |-  ( ( ( ( N ` ( ( A G B ) G ( 1 S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( 1 S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) ) = ( ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) ) | 
						
							| 66 | 56 | oveq2i |  |-  ( A G ( 1 S C ) ) = ( A G C ) | 
						
							| 67 | 66 | fveq2i |  |-  ( N ` ( A G ( 1 S C ) ) ) = ( N ` ( A G C ) ) | 
						
							| 68 | 67 | oveq1i |  |-  ( ( N ` ( A G ( 1 S C ) ) ) ^ 2 ) = ( ( N ` ( A G C ) ) ^ 2 ) | 
						
							| 69 | 68 | oveq1i |  |-  ( ( ( N ` ( A G ( 1 S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) = ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) | 
						
							| 70 | 69 | oveq2i |  |-  ( 2 x. ( ( ( N ` ( A G ( 1 S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) ) = ( 2 x. ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) ) | 
						
							| 71 | 54 65 70 | 3eqtr3i |  |-  ( ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) ) = ( 2 x. ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) ) | 
						
							| 72 | 1 2 3 4 5 6 7 8 9 35 | ip0i |  |-  ( ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) + ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) = ( 2 x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) | 
						
							| 73 | 72 | oveq2i |  |-  ( _i x. ( ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) + ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) = ( _i x. ( 2 x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) | 
						
							| 74 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( A G B ) e. X ) | 
						
							| 75 | 11 6 7 74 | mp3an |  |-  ( A G B ) e. X | 
						
							| 76 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ ( A G B ) e. X /\ ( _i S C ) e. X ) -> ( ( A G B ) G ( _i S C ) ) e. X ) | 
						
							| 77 | 11 75 37 76 | mp3an |  |-  ( ( A G B ) G ( _i S C ) ) e. X | 
						
							| 78 | 1 9 11 77 | nvcli |  |-  ( N ` ( ( A G B ) G ( _i S C ) ) ) e. RR | 
						
							| 79 | 78 | resqcli |  |-  ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) e. RR | 
						
							| 80 | 79 | recni |  |-  ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) e. CC | 
						
							| 81 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ ( A G B ) e. X /\ ( -u _i S C ) e. X ) -> ( ( A G B ) G ( -u _i S C ) ) e. X ) | 
						
							| 82 | 11 75 45 81 | mp3an |  |-  ( ( A G B ) G ( -u _i S C ) ) e. X | 
						
							| 83 | 1 9 11 82 | nvcli |  |-  ( N ` ( ( A G B ) G ( -u _i S C ) ) ) e. RR | 
						
							| 84 | 83 | resqcli |  |-  ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) e. RR | 
						
							| 85 | 84 | recni |  |-  ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) e. CC | 
						
							| 86 | 80 85 | subcli |  |-  ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) e. CC | 
						
							| 87 | 1 3 | nvscl |  |-  ( ( U e. NrmCVec /\ -u 1 e. CC /\ B e. X ) -> ( -u 1 S B ) e. X ) | 
						
							| 88 | 11 26 7 87 | mp3an |  |-  ( -u 1 S B ) e. X | 
						
							| 89 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ A e. X /\ ( -u 1 S B ) e. X ) -> ( A G ( -u 1 S B ) ) e. X ) | 
						
							| 90 | 11 6 88 89 | mp3an |  |-  ( A G ( -u 1 S B ) ) e. X | 
						
							| 91 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ ( A G ( -u 1 S B ) ) e. X /\ ( _i S C ) e. X ) -> ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) e. X ) | 
						
							| 92 | 11 90 37 91 | mp3an |  |-  ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) e. X | 
						
							| 93 | 1 9 11 92 | nvcli |  |-  ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) e. RR | 
						
							| 94 | 93 | resqcli |  |-  ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) e. RR | 
						
							| 95 | 94 | recni |  |-  ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) e. CC | 
						
							| 96 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ ( A G ( -u 1 S B ) ) e. X /\ ( -u _i S C ) e. X ) -> ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) e. X ) | 
						
							| 97 | 11 90 45 96 | mp3an |  |-  ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) e. X | 
						
							| 98 | 1 9 11 97 | nvcli |  |-  ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) e. RR | 
						
							| 99 | 98 | resqcli |  |-  ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) e. RR | 
						
							| 100 | 99 | recni |  |-  ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) e. CC | 
						
							| 101 | 95 100 | subcli |  |-  ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) e. CC | 
						
							| 102 | 35 86 101 | adddii |  |-  ( _i x. ( ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) + ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) = ( ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) + ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) | 
						
							| 103 | 35 15 51 | mul12i |  |-  ( _i x. ( 2 x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) = ( 2 x. ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) | 
						
							| 104 | 73 102 103 | 3eqtr3i |  |-  ( ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) + ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) = ( 2 x. ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) | 
						
							| 105 | 71 104 | oveq12i |  |-  ( ( ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) ) + ( ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) + ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) = ( ( 2 x. ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) ) + ( 2 x. ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) | 
						
							| 106 | 53 105 | eqtr4i |  |-  ( 2 x. ( ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) = ( ( ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) ) + ( ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) + ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) | 
						
							| 107 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ ( A G B ) e. X /\ C e. X ) -> ( ( A G B ) G C ) e. X ) | 
						
							| 108 | 11 75 8 107 | mp3an |  |-  ( ( A G B ) G C ) e. X | 
						
							| 109 | 1 9 11 108 | nvcli |  |-  ( N ` ( ( A G B ) G C ) ) e. RR | 
						
							| 110 | 109 | resqcli |  |-  ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) e. RR | 
						
							| 111 | 110 | recni |  |-  ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) e. CC | 
						
							| 112 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ ( A G B ) e. X /\ ( -u 1 S C ) e. X ) -> ( ( A G B ) G ( -u 1 S C ) ) e. X ) | 
						
							| 113 | 11 75 28 112 | mp3an |  |-  ( ( A G B ) G ( -u 1 S C ) ) e. X | 
						
							| 114 | 1 9 11 113 | nvcli |  |-  ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) e. RR | 
						
							| 115 | 114 | resqcli |  |-  ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) e. RR | 
						
							| 116 | 115 | recni |  |-  ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) e. CC | 
						
							| 117 | 111 116 | subcli |  |-  ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) e. CC | 
						
							| 118 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ ( A G ( -u 1 S B ) ) e. X /\ C e. X ) -> ( ( A G ( -u 1 S B ) ) G C ) e. X ) | 
						
							| 119 | 11 90 8 118 | mp3an |  |-  ( ( A G ( -u 1 S B ) ) G C ) e. X | 
						
							| 120 | 1 9 11 119 | nvcli |  |-  ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) e. RR | 
						
							| 121 | 120 | resqcli |  |-  ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) e. RR | 
						
							| 122 | 121 | recni |  |-  ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) e. CC | 
						
							| 123 | 1 2 | nvgcl |  |-  ( ( U e. NrmCVec /\ ( A G ( -u 1 S B ) ) e. X /\ ( -u 1 S C ) e. X ) -> ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) e. X ) | 
						
							| 124 | 11 90 28 123 | mp3an |  |-  ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) e. X | 
						
							| 125 | 1 9 11 124 | nvcli |  |-  ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) e. RR | 
						
							| 126 | 125 | resqcli |  |-  ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) e. RR | 
						
							| 127 | 126 | recni |  |-  ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) e. CC | 
						
							| 128 | 122 127 | subcli |  |-  ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) e. CC | 
						
							| 129 | 35 86 | mulcli |  |-  ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) e. CC | 
						
							| 130 | 35 101 | mulcli |  |-  ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) e. CC | 
						
							| 131 | 117 128 129 130 | add4i |  |-  ( ( ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) ) + ( ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) + ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) = ( ( ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) + ( ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) | 
						
							| 132 | 1 4 | dipcl |  |-  ( ( U e. NrmCVec /\ ( A G B ) e. X /\ C e. X ) -> ( ( A G B ) P C ) e. CC ) | 
						
							| 133 | 11 75 8 132 | mp3an |  |-  ( ( A G B ) P C ) e. CC | 
						
							| 134 | 1 4 | dipcl |  |-  ( ( U e. NrmCVec /\ ( A G ( -u 1 S B ) ) e. X /\ C e. X ) -> ( ( A G ( -u 1 S B ) ) P C ) e. CC ) | 
						
							| 135 | 11 90 8 134 | mp3an |  |-  ( ( A G ( -u 1 S B ) ) P C ) e. CC | 
						
							| 136 | 16 133 135 | adddii |  |-  ( 4 x. ( ( ( A G B ) P C ) + ( ( A G ( -u 1 S B ) ) P C ) ) ) = ( ( 4 x. ( ( A G B ) P C ) ) + ( 4 x. ( ( A G ( -u 1 S B ) ) P C ) ) ) | 
						
							| 137 | 1 2 3 9 4 | 4ipval2 |  |-  ( ( U e. NrmCVec /\ ( A G B ) e. X /\ C e. X ) -> ( 4 x. ( ( A G B ) P C ) ) = ( ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) | 
						
							| 138 | 11 75 8 137 | mp3an |  |-  ( 4 x. ( ( A G B ) P C ) ) = ( ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) | 
						
							| 139 | 1 2 3 9 4 | 4ipval2 |  |-  ( ( U e. NrmCVec /\ ( A G ( -u 1 S B ) ) e. X /\ C e. X ) -> ( 4 x. ( ( A G ( -u 1 S B ) ) P C ) ) = ( ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) | 
						
							| 140 | 11 90 8 139 | mp3an |  |-  ( 4 x. ( ( A G ( -u 1 S B ) ) P C ) ) = ( ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) | 
						
							| 141 | 138 140 | oveq12i |  |-  ( ( 4 x. ( ( A G B ) P C ) ) + ( 4 x. ( ( A G ( -u 1 S B ) ) P C ) ) ) = ( ( ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) + ( ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) | 
						
							| 142 | 136 141 | eqtr2i |  |-  ( ( ( ( ( N ` ( ( A G B ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( ( A G B ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G B ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) + ( ( ( ( N ` ( ( A G ( -u 1 S B ) ) G C ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( ( A G ( -u 1 S B ) ) G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( ( A G ( -u 1 S B ) ) G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) = ( 4 x. ( ( ( A G B ) P C ) + ( ( A G ( -u 1 S B ) ) P C ) ) ) | 
						
							| 143 | 106 131 142 | 3eqtri |  |-  ( 2 x. ( ( ( ( N ` ( A G C ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S C ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S C ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S C ) ) ) ^ 2 ) ) ) ) ) = ( 4 x. ( ( ( A G B ) P C ) + ( ( A G ( -u 1 S B ) ) P C ) ) ) | 
						
							| 144 | 14 19 143 | 3eqtr3ri |  |-  ( 4 x. ( ( ( A G B ) P C ) + ( ( A G ( -u 1 S B ) ) P C ) ) ) = ( 4 x. ( 2 x. ( A P C ) ) ) | 
						
							| 145 | 144 | oveq1i |  |-  ( ( 4 x. ( ( ( A G B ) P C ) + ( ( A G ( -u 1 S B ) ) P C ) ) ) / 4 ) = ( ( 4 x. ( 2 x. ( A P C ) ) ) / 4 ) | 
						
							| 146 | 133 135 | addcli |  |-  ( ( ( A G B ) P C ) + ( ( A G ( -u 1 S B ) ) P C ) ) e. CC | 
						
							| 147 |  | 4ne0 |  |-  4 =/= 0 | 
						
							| 148 | 146 16 147 | divcan3i |  |-  ( ( 4 x. ( ( ( A G B ) P C ) + ( ( A G ( -u 1 S B ) ) P C ) ) ) / 4 ) = ( ( ( A G B ) P C ) + ( ( A G ( -u 1 S B ) ) P C ) ) | 
						
							| 149 | 15 18 | mulcli |  |-  ( 2 x. ( A P C ) ) e. CC | 
						
							| 150 | 149 16 147 | divcan3i |  |-  ( ( 4 x. ( 2 x. ( A P C ) ) ) / 4 ) = ( 2 x. ( A P C ) ) | 
						
							| 151 | 145 148 150 | 3eqtr3i |  |-  ( ( ( A G B ) P C ) + ( ( A G ( -u 1 S B ) ) P C ) ) = ( 2 x. ( A P C ) ) |