| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mdettpos.d |  |-  D = ( N maDet R ) | 
						
							| 2 |  | mdettpos.a |  |-  A = ( N Mat R ) | 
						
							| 3 |  | mdettpos.b |  |-  B = ( Base ` A ) | 
						
							| 4 |  | ovtpos |  |-  ( ( p ` x ) tpos M x ) = ( x M ( p ` x ) ) | 
						
							| 5 | 4 | mpteq2i |  |-  ( x e. N |-> ( ( p ` x ) tpos M x ) ) = ( x e. N |-> ( x M ( p ` x ) ) ) | 
						
							| 6 | 5 | oveq2i |  |-  ( ( mulGrp ` R ) gsum ( x e. N |-> ( ( p ` x ) tpos M x ) ) ) = ( ( mulGrp ` R ) gsum ( x e. N |-> ( x M ( p ` x ) ) ) ) | 
						
							| 7 | 6 | oveq2i |  |-  ( ( ( ( ZRHom ` R ) o. ( pmSgn ` N ) ) ` p ) ( .r ` R ) ( ( mulGrp ` R ) gsum ( x e. N |-> ( ( p ` x ) tpos M x ) ) ) ) = ( ( ( ( ZRHom ` R ) o. ( pmSgn ` N ) ) ` p ) ( .r ` R ) ( ( mulGrp ` R ) gsum ( x e. N |-> ( x M ( p ` x ) ) ) ) ) | 
						
							| 8 | 7 | mpteq2i |  |-  ( p e. ( Base ` ( SymGrp ` N ) ) |-> ( ( ( ( ZRHom ` R ) o. ( pmSgn ` N ) ) ` p ) ( .r ` R ) ( ( mulGrp ` R ) gsum ( x e. N |-> ( ( p ` x ) tpos M x ) ) ) ) ) = ( p e. ( Base ` ( SymGrp ` N ) ) |-> ( ( ( ( ZRHom ` R ) o. ( pmSgn ` N ) ) ` p ) ( .r ` R ) ( ( mulGrp ` R ) gsum ( x e. N |-> ( x M ( p ` x ) ) ) ) ) ) | 
						
							| 9 | 8 | oveq2i |  |-  ( R gsum ( p e. ( Base ` ( SymGrp ` N ) ) |-> ( ( ( ( ZRHom ` R ) o. ( pmSgn ` N ) ) ` p ) ( .r ` R ) ( ( mulGrp ` R ) gsum ( x e. N |-> ( ( p ` x ) tpos M x ) ) ) ) ) ) = ( R gsum ( p e. ( Base ` ( SymGrp ` N ) ) |-> ( ( ( ( ZRHom ` R ) o. ( pmSgn ` N ) ) ` p ) ( .r ` R ) ( ( mulGrp ` R ) gsum ( x e. N |-> ( x M ( p ` x ) ) ) ) ) ) ) | 
						
							| 10 | 2 3 | mattposcl |  |-  ( M e. B -> tpos M e. B ) | 
						
							| 11 | 10 | adantl |  |-  ( ( R e. CRing /\ M e. B ) -> tpos M e. B ) | 
						
							| 12 |  | eqid |  |-  ( Base ` ( SymGrp ` N ) ) = ( Base ` ( SymGrp ` N ) ) | 
						
							| 13 |  | eqid |  |-  ( ZRHom ` R ) = ( ZRHom ` R ) | 
						
							| 14 |  | eqid |  |-  ( pmSgn ` N ) = ( pmSgn ` N ) | 
						
							| 15 |  | eqid |  |-  ( .r ` R ) = ( .r ` R ) | 
						
							| 16 |  | eqid |  |-  ( mulGrp ` R ) = ( mulGrp ` R ) | 
						
							| 17 | 1 2 3 12 13 14 15 16 | mdetleib |  |-  ( tpos M e. B -> ( D ` tpos M ) = ( R gsum ( p e. ( Base ` ( SymGrp ` N ) ) |-> ( ( ( ( ZRHom ` R ) o. ( pmSgn ` N ) ) ` p ) ( .r ` R ) ( ( mulGrp ` R ) gsum ( x e. N |-> ( ( p ` x ) tpos M x ) ) ) ) ) ) ) | 
						
							| 18 | 11 17 | syl |  |-  ( ( R e. CRing /\ M e. B ) -> ( D ` tpos M ) = ( R gsum ( p e. ( Base ` ( SymGrp ` N ) ) |-> ( ( ( ( ZRHom ` R ) o. ( pmSgn ` N ) ) ` p ) ( .r ` R ) ( ( mulGrp ` R ) gsum ( x e. N |-> ( ( p ` x ) tpos M x ) ) ) ) ) ) ) | 
						
							| 19 | 1 2 3 12 13 14 15 16 | mdetleib2 |  |-  ( ( R e. CRing /\ M e. B ) -> ( D ` M ) = ( R gsum ( p e. ( Base ` ( SymGrp ` N ) ) |-> ( ( ( ( ZRHom ` R ) o. ( pmSgn ` N ) ) ` p ) ( .r ` R ) ( ( mulGrp ` R ) gsum ( x e. N |-> ( x M ( p ` x ) ) ) ) ) ) ) ) | 
						
							| 20 | 9 18 19 | 3eqtr4a |  |-  ( ( R e. CRing /\ M e. B ) -> ( D ` tpos M ) = ( D ` M ) ) |