| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dipfval.1 |  |-  X = ( BaseSet ` U ) | 
						
							| 2 |  | dipfval.2 |  |-  G = ( +v ` U ) | 
						
							| 3 |  | dipfval.4 |  |-  S = ( .sOLD ` U ) | 
						
							| 4 |  | dipfval.6 |  |-  N = ( normCV ` U ) | 
						
							| 5 |  | dipfval.7 |  |-  P = ( .iOLD ` U ) | 
						
							| 6 |  | ipval3.3 |  |-  M = ( -v ` U ) | 
						
							| 7 | 1 2 3 4 5 | ipval2 |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( A P B ) = ( ( ( ( ( N ` ( A G B ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S B ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S B ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S B ) ) ) ^ 2 ) ) ) ) / 4 ) ) | 
						
							| 8 | 1 2 3 6 | nvmval |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( A M B ) = ( A G ( -u 1 S B ) ) ) | 
						
							| 9 | 8 | fveq2d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( N ` ( A M B ) ) = ( N ` ( A G ( -u 1 S B ) ) ) ) | 
						
							| 10 | 9 | oveq1d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( ( N ` ( A M B ) ) ^ 2 ) = ( ( N ` ( A G ( -u 1 S B ) ) ) ^ 2 ) ) | 
						
							| 11 | 10 | oveq2d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( ( ( N ` ( A G B ) ) ^ 2 ) - ( ( N ` ( A M B ) ) ^ 2 ) ) = ( ( ( N ` ( A G B ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S B ) ) ) ^ 2 ) ) ) | 
						
							| 12 |  | ax-icn |  |-  _i e. CC | 
						
							| 13 | 1 3 | nvscl |  |-  ( ( U e. NrmCVec /\ _i e. CC /\ B e. X ) -> ( _i S B ) e. X ) | 
						
							| 14 | 12 13 | mp3an2 |  |-  ( ( U e. NrmCVec /\ B e. X ) -> ( _i S B ) e. X ) | 
						
							| 15 | 14 | 3adant2 |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( _i S B ) e. X ) | 
						
							| 16 | 1 2 3 6 | nvmval |  |-  ( ( U e. NrmCVec /\ A e. X /\ ( _i S B ) e. X ) -> ( A M ( _i S B ) ) = ( A G ( -u 1 S ( _i S B ) ) ) ) | 
						
							| 17 | 15 16 | syld3an3 |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( A M ( _i S B ) ) = ( A G ( -u 1 S ( _i S B ) ) ) ) | 
						
							| 18 |  | neg1cn |  |-  -u 1 e. CC | 
						
							| 19 | 1 3 | nvsass |  |-  ( ( U e. NrmCVec /\ ( -u 1 e. CC /\ _i e. CC /\ B e. X ) ) -> ( ( -u 1 x. _i ) S B ) = ( -u 1 S ( _i S B ) ) ) | 
						
							| 20 | 18 19 | mp3anr1 |  |-  ( ( U e. NrmCVec /\ ( _i e. CC /\ B e. X ) ) -> ( ( -u 1 x. _i ) S B ) = ( -u 1 S ( _i S B ) ) ) | 
						
							| 21 | 12 20 | mpanr1 |  |-  ( ( U e. NrmCVec /\ B e. X ) -> ( ( -u 1 x. _i ) S B ) = ( -u 1 S ( _i S B ) ) ) | 
						
							| 22 | 12 | mulm1i |  |-  ( -u 1 x. _i ) = -u _i | 
						
							| 23 | 22 | oveq1i |  |-  ( ( -u 1 x. _i ) S B ) = ( -u _i S B ) | 
						
							| 24 | 21 23 | eqtr3di |  |-  ( ( U e. NrmCVec /\ B e. X ) -> ( -u 1 S ( _i S B ) ) = ( -u _i S B ) ) | 
						
							| 25 | 24 | 3adant2 |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( -u 1 S ( _i S B ) ) = ( -u _i S B ) ) | 
						
							| 26 | 25 | oveq2d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( A G ( -u 1 S ( _i S B ) ) ) = ( A G ( -u _i S B ) ) ) | 
						
							| 27 | 17 26 | eqtrd |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( A M ( _i S B ) ) = ( A G ( -u _i S B ) ) ) | 
						
							| 28 | 27 | fveq2d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( N ` ( A M ( _i S B ) ) ) = ( N ` ( A G ( -u _i S B ) ) ) ) | 
						
							| 29 | 28 | oveq1d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( ( N ` ( A M ( _i S B ) ) ) ^ 2 ) = ( ( N ` ( A G ( -u _i S B ) ) ) ^ 2 ) ) | 
						
							| 30 | 29 | oveq2d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( ( ( N ` ( A G ( _i S B ) ) ) ^ 2 ) - ( ( N ` ( A M ( _i S B ) ) ) ^ 2 ) ) = ( ( ( N ` ( A G ( _i S B ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S B ) ) ) ^ 2 ) ) ) | 
						
							| 31 | 30 | oveq2d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( _i x. ( ( ( N ` ( A G ( _i S B ) ) ) ^ 2 ) - ( ( N ` ( A M ( _i S B ) ) ) ^ 2 ) ) ) = ( _i x. ( ( ( N ` ( A G ( _i S B ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S B ) ) ) ^ 2 ) ) ) ) | 
						
							| 32 | 11 31 | oveq12d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( ( ( ( N ` ( A G B ) ) ^ 2 ) - ( ( N ` ( A M B ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S B ) ) ) ^ 2 ) - ( ( N ` ( A M ( _i S B ) ) ) ^ 2 ) ) ) ) = ( ( ( ( N ` ( A G B ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S B ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S B ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S B ) ) ) ^ 2 ) ) ) ) ) | 
						
							| 33 | 32 | oveq1d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( ( ( ( ( N ` ( A G B ) ) ^ 2 ) - ( ( N ` ( A M B ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S B ) ) ) ^ 2 ) - ( ( N ` ( A M ( _i S B ) ) ) ^ 2 ) ) ) ) / 4 ) = ( ( ( ( ( N ` ( A G B ) ) ^ 2 ) - ( ( N ` ( A G ( -u 1 S B ) ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S B ) ) ) ^ 2 ) - ( ( N ` ( A G ( -u _i S B ) ) ) ^ 2 ) ) ) ) / 4 ) ) | 
						
							| 34 | 7 33 | eqtr4d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( A P B ) = ( ( ( ( ( N ` ( A G B ) ) ^ 2 ) - ( ( N ` ( A M B ) ) ^ 2 ) ) + ( _i x. ( ( ( N ` ( A G ( _i S B ) ) ) ^ 2 ) - ( ( N ` ( A M ( _i S B ) ) ) ^ 2 ) ) ) ) / 4 ) ) |