| Step | Hyp | Ref | Expression | 
						
							| 1 |  | fundcmpsurinj.p |  |-  P = { z | E. x e. A z = ( `' F " { ( F ` x ) } ) } | 
						
							| 2 |  | fundcmpsurinj.h |  |-  H = ( p e. P |-> U. ( F " p ) ) | 
						
							| 3 | 1 2 | imasetpreimafvbijlemf |  |-  ( F Fn A -> H : P --> ( F " A ) ) | 
						
							| 4 | 3 | adantr |  |-  ( ( F Fn A /\ A e. V ) -> H : P --> ( F " A ) ) | 
						
							| 5 | 1 | preimafvelsetpreimafv |  |-  ( ( F Fn A /\ A e. V /\ a e. A ) -> ( `' F " { ( F ` a ) } ) e. P ) | 
						
							| 6 | 5 | 3expa |  |-  ( ( ( F Fn A /\ A e. V ) /\ a e. A ) -> ( `' F " { ( F ` a ) } ) e. P ) | 
						
							| 7 |  | imaeq2 |  |-  ( p = ( `' F " { ( F ` a ) } ) -> ( F " p ) = ( F " ( `' F " { ( F ` a ) } ) ) ) | 
						
							| 8 | 7 | unieqd |  |-  ( p = ( `' F " { ( F ` a ) } ) -> U. ( F " p ) = U. ( F " ( `' F " { ( F ` a ) } ) ) ) | 
						
							| 9 | 8 | eqeq2d |  |-  ( p = ( `' F " { ( F ` a ) } ) -> ( ( F ` a ) = U. ( F " p ) <-> ( F ` a ) = U. ( F " ( `' F " { ( F ` a ) } ) ) ) ) | 
						
							| 10 | 9 | adantl |  |-  ( ( ( ( F Fn A /\ A e. V ) /\ a e. A ) /\ p = ( `' F " { ( F ` a ) } ) ) -> ( ( F ` a ) = U. ( F " p ) <-> ( F ` a ) = U. ( F " ( `' F " { ( F ` a ) } ) ) ) ) | 
						
							| 11 |  | uniimaprimaeqfv |  |-  ( ( F Fn A /\ a e. A ) -> U. ( F " ( `' F " { ( F ` a ) } ) ) = ( F ` a ) ) | 
						
							| 12 | 11 | adantlr |  |-  ( ( ( F Fn A /\ A e. V ) /\ a e. A ) -> U. ( F " ( `' F " { ( F ` a ) } ) ) = ( F ` a ) ) | 
						
							| 13 | 12 | eqcomd |  |-  ( ( ( F Fn A /\ A e. V ) /\ a e. A ) -> ( F ` a ) = U. ( F " ( `' F " { ( F ` a ) } ) ) ) | 
						
							| 14 | 6 10 13 | rspcedvd |  |-  ( ( ( F Fn A /\ A e. V ) /\ a e. A ) -> E. p e. P ( F ` a ) = U. ( F " p ) ) | 
						
							| 15 |  | eqeq1 |  |-  ( y = ( F ` a ) -> ( y = U. ( F " p ) <-> ( F ` a ) = U. ( F " p ) ) ) | 
						
							| 16 | 15 | eqcoms |  |-  ( ( F ` a ) = y -> ( y = U. ( F " p ) <-> ( F ` a ) = U. ( F " p ) ) ) | 
						
							| 17 | 16 | rexbidv |  |-  ( ( F ` a ) = y -> ( E. p e. P y = U. ( F " p ) <-> E. p e. P ( F ` a ) = U. ( F " p ) ) ) | 
						
							| 18 | 14 17 | syl5ibrcom |  |-  ( ( ( F Fn A /\ A e. V ) /\ a e. A ) -> ( ( F ` a ) = y -> E. p e. P y = U. ( F " p ) ) ) | 
						
							| 19 | 18 | rexlimdva |  |-  ( ( F Fn A /\ A e. V ) -> ( E. a e. A ( F ` a ) = y -> E. p e. P y = U. ( F " p ) ) ) | 
						
							| 20 | 8 | eqcomd |  |-  ( p = ( `' F " { ( F ` a ) } ) -> U. ( F " ( `' F " { ( F ` a ) } ) ) = U. ( F " p ) ) | 
						
							| 21 | 13 20 | sylan9eq |  |-  ( ( ( ( F Fn A /\ A e. V ) /\ a e. A ) /\ p = ( `' F " { ( F ` a ) } ) ) -> ( F ` a ) = U. ( F " p ) ) | 
						
							| 22 | 21 | ex |  |-  ( ( ( F Fn A /\ A e. V ) /\ a e. A ) -> ( p = ( `' F " { ( F ` a ) } ) -> ( F ` a ) = U. ( F " p ) ) ) | 
						
							| 23 | 22 | reximdva |  |-  ( ( F Fn A /\ A e. V ) -> ( E. a e. A p = ( `' F " { ( F ` a ) } ) -> E. a e. A ( F ` a ) = U. ( F " p ) ) ) | 
						
							| 24 | 1 | elsetpreimafv |  |-  ( p e. P -> E. x e. A p = ( `' F " { ( F ` x ) } ) ) | 
						
							| 25 |  | fveq2 |  |-  ( a = x -> ( F ` a ) = ( F ` x ) ) | 
						
							| 26 | 25 | sneqd |  |-  ( a = x -> { ( F ` a ) } = { ( F ` x ) } ) | 
						
							| 27 | 26 | imaeq2d |  |-  ( a = x -> ( `' F " { ( F ` a ) } ) = ( `' F " { ( F ` x ) } ) ) | 
						
							| 28 | 27 | eqeq2d |  |-  ( a = x -> ( p = ( `' F " { ( F ` a ) } ) <-> p = ( `' F " { ( F ` x ) } ) ) ) | 
						
							| 29 | 28 | cbvrexvw |  |-  ( E. a e. A p = ( `' F " { ( F ` a ) } ) <-> E. x e. A p = ( `' F " { ( F ` x ) } ) ) | 
						
							| 30 | 24 29 | sylibr |  |-  ( p e. P -> E. a e. A p = ( `' F " { ( F ` a ) } ) ) | 
						
							| 31 | 23 30 | impel |  |-  ( ( ( F Fn A /\ A e. V ) /\ p e. P ) -> E. a e. A ( F ` a ) = U. ( F " p ) ) | 
						
							| 32 |  | eqeq2 |  |-  ( y = U. ( F " p ) -> ( ( F ` a ) = y <-> ( F ` a ) = U. ( F " p ) ) ) | 
						
							| 33 | 32 | rexbidv |  |-  ( y = U. ( F " p ) -> ( E. a e. A ( F ` a ) = y <-> E. a e. A ( F ` a ) = U. ( F " p ) ) ) | 
						
							| 34 | 31 33 | syl5ibrcom |  |-  ( ( ( F Fn A /\ A e. V ) /\ p e. P ) -> ( y = U. ( F " p ) -> E. a e. A ( F ` a ) = y ) ) | 
						
							| 35 | 34 | rexlimdva |  |-  ( ( F Fn A /\ A e. V ) -> ( E. p e. P y = U. ( F " p ) -> E. a e. A ( F ` a ) = y ) ) | 
						
							| 36 | 19 35 | impbid |  |-  ( ( F Fn A /\ A e. V ) -> ( E. a e. A ( F ` a ) = y <-> E. p e. P y = U. ( F " p ) ) ) | 
						
							| 37 | 36 | abbidv |  |-  ( ( F Fn A /\ A e. V ) -> { y | E. a e. A ( F ` a ) = y } = { y | E. p e. P y = U. ( F " p ) } ) | 
						
							| 38 |  | fnfun |  |-  ( F Fn A -> Fun F ) | 
						
							| 39 |  | fndm |  |-  ( F Fn A -> dom F = A ) | 
						
							| 40 |  | eqimss2 |  |-  ( dom F = A -> A C_ dom F ) | 
						
							| 41 | 39 40 | syl |  |-  ( F Fn A -> A C_ dom F ) | 
						
							| 42 | 38 41 | jca |  |-  ( F Fn A -> ( Fun F /\ A C_ dom F ) ) | 
						
							| 43 | 42 | adantr |  |-  ( ( F Fn A /\ A e. V ) -> ( Fun F /\ A C_ dom F ) ) | 
						
							| 44 |  | dfimafn |  |-  ( ( Fun F /\ A C_ dom F ) -> ( F " A ) = { y | E. a e. A ( F ` a ) = y } ) | 
						
							| 45 | 43 44 | syl |  |-  ( ( F Fn A /\ A e. V ) -> ( F " A ) = { y | E. a e. A ( F ` a ) = y } ) | 
						
							| 46 | 2 | rnmpt |  |-  ran H = { y | E. p e. P y = U. ( F " p ) } | 
						
							| 47 | 46 | a1i |  |-  ( ( F Fn A /\ A e. V ) -> ran H = { y | E. p e. P y = U. ( F " p ) } ) | 
						
							| 48 | 37 45 47 | 3eqtr4rd |  |-  ( ( F Fn A /\ A e. V ) -> ran H = ( F " A ) ) | 
						
							| 49 |  | dffo2 |  |-  ( H : P -onto-> ( F " A ) <-> ( H : P --> ( F " A ) /\ ran H = ( F " A ) ) ) | 
						
							| 50 | 4 48 49 | sylanbrc |  |-  ( ( F Fn A /\ A e. V ) -> H : P -onto-> ( F " A ) ) |