| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ipcl.1 |  |-  X = ( BaseSet ` U ) | 
						
							| 2 |  | ipcl.7 |  |-  P = ( .iOLD ` U ) | 
						
							| 3 | 1 2 | dipcl |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( A P B ) e. CC ) | 
						
							| 4 | 3 | absvalsqd |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( ( abs ` ( A P B ) ) ^ 2 ) = ( ( A P B ) x. ( * ` ( A P B ) ) ) ) | 
						
							| 5 | 1 2 | dipcj |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( * ` ( A P B ) ) = ( B P A ) ) | 
						
							| 6 | 5 | oveq2d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( ( A P B ) x. ( * ` ( A P B ) ) ) = ( ( A P B ) x. ( B P A ) ) ) | 
						
							| 7 | 4 6 | eqtr2d |  |-  ( ( U e. NrmCVec /\ A e. X /\ B e. X ) -> ( ( A P B ) x. ( B P A ) ) = ( ( abs ` ( A P B ) ) ^ 2 ) ) |