| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mstaval.r |  |-  R = ( mStRed ` T ) | 
						
							| 2 |  | mstaval.s |  |-  S = ( mStat ` T ) | 
						
							| 3 |  | eqid |  |-  ( mPreSt ` T ) = ( mPreSt ` T ) | 
						
							| 4 | 3 1 | msrf |  |-  R : ( mPreSt ` T ) --> ( mPreSt ` T ) | 
						
							| 5 |  | ffn |  |-  ( R : ( mPreSt ` T ) --> ( mPreSt ` T ) -> R Fn ( mPreSt ` T ) ) | 
						
							| 6 |  | fvelrnb |  |-  ( R Fn ( mPreSt ` T ) -> ( X e. ran R <-> E. s e. ( mPreSt ` T ) ( R ` s ) = X ) ) | 
						
							| 7 | 4 5 6 | mp2b |  |-  ( X e. ran R <-> E. s e. ( mPreSt ` T ) ( R ` s ) = X ) | 
						
							| 8 | 3 | mpst123 |  |-  ( s e. ( mPreSt ` T ) -> s = <. ( 1st ` ( 1st ` s ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) | 
						
							| 9 | 8 | fveq2d |  |-  ( s e. ( mPreSt ` T ) -> ( R ` s ) = ( R ` <. ( 1st ` ( 1st ` s ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) ) | 
						
							| 10 |  | id |  |-  ( s e. ( mPreSt ` T ) -> s e. ( mPreSt ` T ) ) | 
						
							| 11 | 8 10 | eqeltrrd |  |-  ( s e. ( mPreSt ` T ) -> <. ( 1st ` ( 1st ` s ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. e. ( mPreSt ` T ) ) | 
						
							| 12 |  | eqid |  |-  ( mVars ` T ) = ( mVars ` T ) | 
						
							| 13 |  | eqid |  |-  U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) = U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) | 
						
							| 14 | 12 3 1 13 | msrval |  |-  ( <. ( 1st ` ( 1st ` s ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. e. ( mPreSt ` T ) -> ( R ` <. ( 1st ` ( 1st ` s ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) = <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) | 
						
							| 15 | 11 14 | syl |  |-  ( s e. ( mPreSt ` T ) -> ( R ` <. ( 1st ` ( 1st ` s ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) = <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) | 
						
							| 16 | 9 15 | eqtrd |  |-  ( s e. ( mPreSt ` T ) -> ( R ` s ) = <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) | 
						
							| 17 | 4 | ffvelcdmi |  |-  ( s e. ( mPreSt ` T ) -> ( R ` s ) e. ( mPreSt ` T ) ) | 
						
							| 18 | 16 17 | eqeltrrd |  |-  ( s e. ( mPreSt ` T ) -> <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. e. ( mPreSt ` T ) ) | 
						
							| 19 | 12 3 1 13 | msrval |  |-  ( <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. e. ( mPreSt ` T ) -> ( R ` <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) = <. ( ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) | 
						
							| 20 | 18 19 | syl |  |-  ( s e. ( mPreSt ` T ) -> ( R ` <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) = <. ( ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) | 
						
							| 21 |  | inass |  |-  ( ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) = ( ( 1st ` ( 1st ` s ) ) i^i ( ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) ) | 
						
							| 22 |  | inidm |  |-  ( ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) = ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) | 
						
							| 23 | 22 | ineq2i |  |-  ( ( 1st ` ( 1st ` s ) ) i^i ( ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) ) = ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) | 
						
							| 24 | 21 23 | eqtri |  |-  ( ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) = ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) | 
						
							| 25 | 24 | a1i |  |-  ( s e. ( mPreSt ` T ) -> ( ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) = ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) ) | 
						
							| 26 | 25 | oteq1d |  |-  ( s e. ( mPreSt ` T ) -> <. ( ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. = <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) | 
						
							| 27 | 20 26 | eqtrd |  |-  ( s e. ( mPreSt ` T ) -> ( R ` <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) = <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) | 
						
							| 28 | 16 | fveq2d |  |-  ( s e. ( mPreSt ` T ) -> ( R ` ( R ` s ) ) = ( R ` <. ( ( 1st ` ( 1st ` s ) ) i^i ( U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) X. U. ( ( mVars ` T ) " ( ( 2nd ` ( 1st ` s ) ) u. { ( 2nd ` s ) } ) ) ) ) , ( 2nd ` ( 1st ` s ) ) , ( 2nd ` s ) >. ) ) | 
						
							| 29 | 27 28 16 | 3eqtr4d |  |-  ( s e. ( mPreSt ` T ) -> ( R ` ( R ` s ) ) = ( R ` s ) ) | 
						
							| 30 |  | fveq2 |  |-  ( ( R ` s ) = X -> ( R ` ( R ` s ) ) = ( R ` X ) ) | 
						
							| 31 |  | id |  |-  ( ( R ` s ) = X -> ( R ` s ) = X ) | 
						
							| 32 | 30 31 | eqeq12d |  |-  ( ( R ` s ) = X -> ( ( R ` ( R ` s ) ) = ( R ` s ) <-> ( R ` X ) = X ) ) | 
						
							| 33 | 29 32 | syl5ibcom |  |-  ( s e. ( mPreSt ` T ) -> ( ( R ` s ) = X -> ( R ` X ) = X ) ) | 
						
							| 34 | 33 | rexlimiv |  |-  ( E. s e. ( mPreSt ` T ) ( R ` s ) = X -> ( R ` X ) = X ) | 
						
							| 35 | 7 34 | sylbi |  |-  ( X e. ran R -> ( R ` X ) = X ) | 
						
							| 36 | 1 2 | mstaval |  |-  S = ran R | 
						
							| 37 | 35 36 | eleq2s |  |-  ( X e. S -> ( R ` X ) = X ) |