| Step | Hyp | Ref | Expression | 
						
							| 1 |  | df-sate |  |-  SatE = ( m e. _V , u e. _V |-> ( ( ( m Sat ( _E i^i ( m X. m ) ) ) ` _om ) ` u ) ) | 
						
							| 2 | 1 | a1i |  |-  ( ( M e. V /\ U e. W ) -> SatE = ( m e. _V , u e. _V |-> ( ( ( m Sat ( _E i^i ( m X. m ) ) ) ` _om ) ` u ) ) ) | 
						
							| 3 |  | id |  |-  ( m = M -> m = M ) | 
						
							| 4 | 3 | sqxpeqd |  |-  ( m = M -> ( m X. m ) = ( M X. M ) ) | 
						
							| 5 | 4 | ineq2d |  |-  ( m = M -> ( _E i^i ( m X. m ) ) = ( _E i^i ( M X. M ) ) ) | 
						
							| 6 | 3 5 | oveq12d |  |-  ( m = M -> ( m Sat ( _E i^i ( m X. m ) ) ) = ( M Sat ( _E i^i ( M X. M ) ) ) ) | 
						
							| 7 | 6 | fveq1d |  |-  ( m = M -> ( ( m Sat ( _E i^i ( m X. m ) ) ) ` _om ) = ( ( M Sat ( _E i^i ( M X. M ) ) ) ` _om ) ) | 
						
							| 8 | 7 | adantr |  |-  ( ( m = M /\ u = U ) -> ( ( m Sat ( _E i^i ( m X. m ) ) ) ` _om ) = ( ( M Sat ( _E i^i ( M X. M ) ) ) ` _om ) ) | 
						
							| 9 |  | simpr |  |-  ( ( m = M /\ u = U ) -> u = U ) | 
						
							| 10 | 8 9 | fveq12d |  |-  ( ( m = M /\ u = U ) -> ( ( ( m Sat ( _E i^i ( m X. m ) ) ) ` _om ) ` u ) = ( ( ( M Sat ( _E i^i ( M X. M ) ) ) ` _om ) ` U ) ) | 
						
							| 11 | 10 | adantl |  |-  ( ( ( M e. V /\ U e. W ) /\ ( m = M /\ u = U ) ) -> ( ( ( m Sat ( _E i^i ( m X. m ) ) ) ` _om ) ` u ) = ( ( ( M Sat ( _E i^i ( M X. M ) ) ) ` _om ) ` U ) ) | 
						
							| 12 |  | elex |  |-  ( M e. V -> M e. _V ) | 
						
							| 13 | 12 | adantr |  |-  ( ( M e. V /\ U e. W ) -> M e. _V ) | 
						
							| 14 |  | elex |  |-  ( U e. W -> U e. _V ) | 
						
							| 15 | 14 | adantl |  |-  ( ( M e. V /\ U e. W ) -> U e. _V ) | 
						
							| 16 |  | fvexd |  |-  ( ( M e. V /\ U e. W ) -> ( ( ( M Sat ( _E i^i ( M X. M ) ) ) ` _om ) ` U ) e. _V ) | 
						
							| 17 | 2 11 13 15 16 | ovmpod |  |-  ( ( M e. V /\ U e. W ) -> ( M SatE U ) = ( ( ( M Sat ( _E i^i ( M X. M ) ) ) ` _om ) ` U ) ) |