| Step | Hyp | Ref | Expression | 
						
							| 1 |  | sategoelfvb.s |  |-  E = ( M SatE ( A e.g B ) ) | 
						
							| 2 |  | ovexd |  |-  ( ( A e. _om /\ B e. _om ) -> ( A e.g B ) e. _V ) | 
						
							| 3 |  | simpl |  |-  ( ( A e. _om /\ B e. _om ) -> A e. _om ) | 
						
							| 4 |  | opeq1 |  |-  ( a = A -> <. a , b >. = <. A , b >. ) | 
						
							| 5 | 4 | opeq2d |  |-  ( a = A -> <. (/) , <. a , b >. >. = <. (/) , <. A , b >. >. ) | 
						
							| 6 | 5 | eqeq2d |  |-  ( a = A -> ( <. (/) , <. A , B >. >. = <. (/) , <. a , b >. >. <-> <. (/) , <. A , B >. >. = <. (/) , <. A , b >. >. ) ) | 
						
							| 7 | 6 | rexbidv |  |-  ( a = A -> ( E. b e. _om <. (/) , <. A , B >. >. = <. (/) , <. a , b >. >. <-> E. b e. _om <. (/) , <. A , B >. >. = <. (/) , <. A , b >. >. ) ) | 
						
							| 8 | 7 | adantl |  |-  ( ( ( A e. _om /\ B e. _om ) /\ a = A ) -> ( E. b e. _om <. (/) , <. A , B >. >. = <. (/) , <. a , b >. >. <-> E. b e. _om <. (/) , <. A , B >. >. = <. (/) , <. A , b >. >. ) ) | 
						
							| 9 |  | simpr |  |-  ( ( A e. _om /\ B e. _om ) -> B e. _om ) | 
						
							| 10 |  | opeq2 |  |-  ( b = B -> <. A , b >. = <. A , B >. ) | 
						
							| 11 | 10 | opeq2d |  |-  ( b = B -> <. (/) , <. A , b >. >. = <. (/) , <. A , B >. >. ) | 
						
							| 12 | 11 | eqeq2d |  |-  ( b = B -> ( <. (/) , <. A , B >. >. = <. (/) , <. A , b >. >. <-> <. (/) , <. A , B >. >. = <. (/) , <. A , B >. >. ) ) | 
						
							| 13 | 12 | adantl |  |-  ( ( ( A e. _om /\ B e. _om ) /\ b = B ) -> ( <. (/) , <. A , B >. >. = <. (/) , <. A , b >. >. <-> <. (/) , <. A , B >. >. = <. (/) , <. A , B >. >. ) ) | 
						
							| 14 |  | eqidd |  |-  ( ( A e. _om /\ B e. _om ) -> <. (/) , <. A , B >. >. = <. (/) , <. A , B >. >. ) | 
						
							| 15 | 9 13 14 | rspcedvd |  |-  ( ( A e. _om /\ B e. _om ) -> E. b e. _om <. (/) , <. A , B >. >. = <. (/) , <. A , b >. >. ) | 
						
							| 16 | 3 8 15 | rspcedvd |  |-  ( ( A e. _om /\ B e. _om ) -> E. a e. _om E. b e. _om <. (/) , <. A , B >. >. = <. (/) , <. a , b >. >. ) | 
						
							| 17 |  | goel |  |-  ( ( A e. _om /\ B e. _om ) -> ( A e.g B ) = <. (/) , <. A , B >. >. ) | 
						
							| 18 |  | goel |  |-  ( ( a e. _om /\ b e. _om ) -> ( a e.g b ) = <. (/) , <. a , b >. >. ) | 
						
							| 19 | 17 18 | eqeqan12d |  |-  ( ( ( A e. _om /\ B e. _om ) /\ ( a e. _om /\ b e. _om ) ) -> ( ( A e.g B ) = ( a e.g b ) <-> <. (/) , <. A , B >. >. = <. (/) , <. a , b >. >. ) ) | 
						
							| 20 | 19 | 2rexbidva |  |-  ( ( A e. _om /\ B e. _om ) -> ( E. a e. _om E. b e. _om ( A e.g B ) = ( a e.g b ) <-> E. a e. _om E. b e. _om <. (/) , <. A , B >. >. = <. (/) , <. a , b >. >. ) ) | 
						
							| 21 | 16 20 | mpbird |  |-  ( ( A e. _om /\ B e. _om ) -> E. a e. _om E. b e. _om ( A e.g B ) = ( a e.g b ) ) | 
						
							| 22 |  | eqeq1 |  |-  ( x = ( A e.g B ) -> ( x = ( a e.g b ) <-> ( A e.g B ) = ( a e.g b ) ) ) | 
						
							| 23 | 22 | 2rexbidv |  |-  ( x = ( A e.g B ) -> ( E. a e. _om E. b e. _om x = ( a e.g b ) <-> E. a e. _om E. b e. _om ( A e.g B ) = ( a e.g b ) ) ) | 
						
							| 24 |  | fmla0 |  |-  ( Fmla ` (/) ) = { x e. _V | E. a e. _om E. b e. _om x = ( a e.g b ) } | 
						
							| 25 | 23 24 | elrab2 |  |-  ( ( A e.g B ) e. ( Fmla ` (/) ) <-> ( ( A e.g B ) e. _V /\ E. a e. _om E. b e. _om ( A e.g B ) = ( a e.g b ) ) ) | 
						
							| 26 | 2 21 25 | sylanbrc |  |-  ( ( A e. _om /\ B e. _om ) -> ( A e.g B ) e. ( Fmla ` (/) ) ) | 
						
							| 27 |  | satefvfmla0 |  |-  ( ( M e. V /\ ( A e.g B ) e. ( Fmla ` (/) ) ) -> ( M SatE ( A e.g B ) ) = { a e. ( M ^m _om ) | ( a ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( a ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) } ) | 
						
							| 28 | 26 27 | sylan2 |  |-  ( ( M e. V /\ ( A e. _om /\ B e. _om ) ) -> ( M SatE ( A e.g B ) ) = { a e. ( M ^m _om ) | ( a ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( a ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) } ) | 
						
							| 29 | 1 28 | eqtrid |  |-  ( ( M e. V /\ ( A e. _om /\ B e. _om ) ) -> E = { a e. ( M ^m _om ) | ( a ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( a ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) } ) | 
						
							| 30 | 29 | eleq2d |  |-  ( ( M e. V /\ ( A e. _om /\ B e. _om ) ) -> ( S e. E <-> S e. { a e. ( M ^m _om ) | ( a ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( a ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) } ) ) | 
						
							| 31 |  | fveq1 |  |-  ( a = S -> ( a ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) = ( S ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) ) | 
						
							| 32 |  | fveq1 |  |-  ( a = S -> ( a ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) = ( S ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) ) | 
						
							| 33 | 31 32 | eleq12d |  |-  ( a = S -> ( ( a ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( a ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) <-> ( S ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( S ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) ) ) | 
						
							| 34 | 33 | elrab |  |-  ( S e. { a e. ( M ^m _om ) | ( a ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( a ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) } <-> ( S e. ( M ^m _om ) /\ ( S ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( S ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) ) ) | 
						
							| 35 | 30 34 | bitrdi |  |-  ( ( M e. V /\ ( A e. _om /\ B e. _om ) ) -> ( S e. E <-> ( S e. ( M ^m _om ) /\ ( S ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( S ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) ) ) ) | 
						
							| 36 | 17 | fveq2d |  |-  ( ( A e. _om /\ B e. _om ) -> ( 2nd ` ( A e.g B ) ) = ( 2nd ` <. (/) , <. A , B >. >. ) ) | 
						
							| 37 | 36 | fveq2d |  |-  ( ( A e. _om /\ B e. _om ) -> ( 1st ` ( 2nd ` ( A e.g B ) ) ) = ( 1st ` ( 2nd ` <. (/) , <. A , B >. >. ) ) ) | 
						
							| 38 |  | 0ex |  |-  (/) e. _V | 
						
							| 39 |  | opex |  |-  <. A , B >. e. _V | 
						
							| 40 | 38 39 | op2nd |  |-  ( 2nd ` <. (/) , <. A , B >. >. ) = <. A , B >. | 
						
							| 41 | 40 | fveq2i |  |-  ( 1st ` ( 2nd ` <. (/) , <. A , B >. >. ) ) = ( 1st ` <. A , B >. ) | 
						
							| 42 |  | op1stg |  |-  ( ( A e. _om /\ B e. _om ) -> ( 1st ` <. A , B >. ) = A ) | 
						
							| 43 | 41 42 | eqtrid |  |-  ( ( A e. _om /\ B e. _om ) -> ( 1st ` ( 2nd ` <. (/) , <. A , B >. >. ) ) = A ) | 
						
							| 44 | 37 43 | eqtrd |  |-  ( ( A e. _om /\ B e. _om ) -> ( 1st ` ( 2nd ` ( A e.g B ) ) ) = A ) | 
						
							| 45 | 44 | fveq2d |  |-  ( ( A e. _om /\ B e. _om ) -> ( S ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) = ( S ` A ) ) | 
						
							| 46 | 36 | fveq2d |  |-  ( ( A e. _om /\ B e. _om ) -> ( 2nd ` ( 2nd ` ( A e.g B ) ) ) = ( 2nd ` ( 2nd ` <. (/) , <. A , B >. >. ) ) ) | 
						
							| 47 | 40 | fveq2i |  |-  ( 2nd ` ( 2nd ` <. (/) , <. A , B >. >. ) ) = ( 2nd ` <. A , B >. ) | 
						
							| 48 |  | op2ndg |  |-  ( ( A e. _om /\ B e. _om ) -> ( 2nd ` <. A , B >. ) = B ) | 
						
							| 49 | 47 48 | eqtrid |  |-  ( ( A e. _om /\ B e. _om ) -> ( 2nd ` ( 2nd ` <. (/) , <. A , B >. >. ) ) = B ) | 
						
							| 50 | 46 49 | eqtrd |  |-  ( ( A e. _om /\ B e. _om ) -> ( 2nd ` ( 2nd ` ( A e.g B ) ) ) = B ) | 
						
							| 51 | 50 | fveq2d |  |-  ( ( A e. _om /\ B e. _om ) -> ( S ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) = ( S ` B ) ) | 
						
							| 52 | 45 51 | eleq12d |  |-  ( ( A e. _om /\ B e. _om ) -> ( ( S ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( S ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) <-> ( S ` A ) e. ( S ` B ) ) ) | 
						
							| 53 | 52 | adantl |  |-  ( ( M e. V /\ ( A e. _om /\ B e. _om ) ) -> ( ( S ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( S ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) <-> ( S ` A ) e. ( S ` B ) ) ) | 
						
							| 54 | 53 | anbi2d |  |-  ( ( M e. V /\ ( A e. _om /\ B e. _om ) ) -> ( ( S e. ( M ^m _om ) /\ ( S ` ( 1st ` ( 2nd ` ( A e.g B ) ) ) ) e. ( S ` ( 2nd ` ( 2nd ` ( A e.g B ) ) ) ) ) <-> ( S e. ( M ^m _om ) /\ ( S ` A ) e. ( S ` B ) ) ) ) | 
						
							| 55 | 35 54 | bitrd |  |-  ( ( M e. V /\ ( A e. _om /\ B e. _om ) ) -> ( S e. E <-> ( S e. ( M ^m _om ) /\ ( S ` A ) e. ( S ` B ) ) ) ) |