| Step | Hyp | Ref | Expression | 
						
							| 1 |  | tfsconcat.op |  |-  .+ = ( a e. _V , b e. _V |-> ( a u. { <. x , y >. | ( x e. ( ( dom a +o dom b ) \ dom a ) /\ E. z e. dom b ( x = ( dom a +o z ) /\ y = ( b ` z ) ) ) } ) ) | 
						
							| 2 |  | dffn3 |  |-  ( F Fn ( C +o D ) <-> F : ( C +o D ) --> ran F ) | 
						
							| 3 | 2 | biimpi |  |-  ( F Fn ( C +o D ) -> F : ( C +o D ) --> ran F ) | 
						
							| 4 | 3 | adantr |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> F : ( C +o D ) --> ran F ) | 
						
							| 5 |  | fndm |  |-  ( F Fn ( C +o D ) -> dom F = ( C +o D ) ) | 
						
							| 6 | 5 | adantr |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> dom F = ( C +o D ) ) | 
						
							| 7 |  | oacl |  |-  ( ( C e. On /\ D e. On ) -> ( C +o D ) e. On ) | 
						
							| 8 | 7 | adantl |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( C +o D ) e. On ) | 
						
							| 9 | 6 8 | eqeltrd |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> dom F e. On ) | 
						
							| 10 |  | fnfun |  |-  ( F Fn ( C +o D ) -> Fun F ) | 
						
							| 11 | 10 | adantr |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> Fun F ) | 
						
							| 12 |  | funrnex |  |-  ( dom F e. On -> ( Fun F -> ran F e. _V ) ) | 
						
							| 13 | 9 11 12 | sylc |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ran F e. _V ) | 
						
							| 14 | 13 8 | elmapd |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( F e. ( ran F ^m ( C +o D ) ) <-> F : ( C +o D ) --> ran F ) ) | 
						
							| 15 | 4 14 | mpbird |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> F e. ( ran F ^m ( C +o D ) ) ) | 
						
							| 16 |  | oaword1 |  |-  ( ( C e. On /\ D e. On ) -> C C_ ( C +o D ) ) | 
						
							| 17 | 16 | adantl |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> C C_ ( C +o D ) ) | 
						
							| 18 |  | elmapssres |  |-  ( ( F e. ( ran F ^m ( C +o D ) ) /\ C C_ ( C +o D ) ) -> ( F |` C ) e. ( ran F ^m C ) ) | 
						
							| 19 | 15 17 18 | syl2anc |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( F |` C ) e. ( ran F ^m C ) ) | 
						
							| 20 |  | simpl |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> F Fn ( C +o D ) ) | 
						
							| 21 |  | oaordi |  |-  ( ( D e. On /\ C e. On ) -> ( d e. D -> ( C +o d ) e. ( C +o D ) ) ) | 
						
							| 22 | 21 | ancoms |  |-  ( ( C e. On /\ D e. On ) -> ( d e. D -> ( C +o d ) e. ( C +o D ) ) ) | 
						
							| 23 | 22 | adantl |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( d e. D -> ( C +o d ) e. ( C +o D ) ) ) | 
						
							| 24 | 23 | imp |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ d e. D ) -> ( C +o d ) e. ( C +o D ) ) | 
						
							| 25 |  | fnfvelrn |  |-  ( ( F Fn ( C +o D ) /\ ( C +o d ) e. ( C +o D ) ) -> ( F ` ( C +o d ) ) e. ran F ) | 
						
							| 26 | 20 24 25 | syl2an2r |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ d e. D ) -> ( F ` ( C +o d ) ) e. ran F ) | 
						
							| 27 | 26 | fmpttd |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( d e. D |-> ( F ` ( C +o d ) ) ) : D --> ran F ) | 
						
							| 28 |  | simprr |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> D e. On ) | 
						
							| 29 | 13 28 | elmapd |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( ( d e. D |-> ( F ` ( C +o d ) ) ) e. ( ran F ^m D ) <-> ( d e. D |-> ( F ` ( C +o d ) ) ) : D --> ran F ) ) | 
						
							| 30 | 27 29 | mpbird |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( d e. D |-> ( F ` ( C +o d ) ) ) e. ( ran F ^m D ) ) | 
						
							| 31 | 20 17 | fnssresd |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( F |` C ) Fn C ) | 
						
							| 32 |  | fvex |  |-  ( F ` ( C +o d ) ) e. _V | 
						
							| 33 |  | eqid |  |-  ( d e. D |-> ( F ` ( C +o d ) ) ) = ( d e. D |-> ( F ` ( C +o d ) ) ) | 
						
							| 34 | 32 33 | fnmpti |  |-  ( d e. D |-> ( F ` ( C +o d ) ) ) Fn D | 
						
							| 35 | 34 | a1i |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( d e. D |-> ( F ` ( C +o d ) ) ) Fn D ) | 
						
							| 36 |  | simpr |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( C e. On /\ D e. On ) ) | 
						
							| 37 | 1 | tfsconcatun |  |-  ( ( ( ( F |` C ) Fn C /\ ( d e. D |-> ( F ` ( C +o d ) ) ) Fn D ) /\ ( C e. On /\ D e. On ) ) -> ( ( F |` C ) .+ ( d e. D |-> ( F ` ( C +o d ) ) ) ) = ( ( F |` C ) u. { <. x , y >. | ( x e. ( ( C +o D ) \ C ) /\ E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) } ) ) | 
						
							| 38 | 31 35 36 37 | syl21anc |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( ( F |` C ) .+ ( d e. D |-> ( F ` ( C +o d ) ) ) ) = ( ( F |` C ) u. { <. x , y >. | ( x e. ( ( C +o D ) \ C ) /\ E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) } ) ) | 
						
							| 39 |  | oveq2 |  |-  ( d = z -> ( C +o d ) = ( C +o z ) ) | 
						
							| 40 | 39 | fveq2d |  |-  ( d = z -> ( F ` ( C +o d ) ) = ( F ` ( C +o z ) ) ) | 
						
							| 41 |  | fvex |  |-  ( F ` ( C +o z ) ) e. _V | 
						
							| 42 | 40 33 41 | fvmpt |  |-  ( z e. D -> ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) = ( F ` ( C +o z ) ) ) | 
						
							| 43 | 42 | ad2antlr |  |-  ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ z e. D ) /\ x = ( C +o z ) ) -> ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) = ( F ` ( C +o z ) ) ) | 
						
							| 44 |  | fveq2 |  |-  ( x = ( C +o z ) -> ( F ` x ) = ( F ` ( C +o z ) ) ) | 
						
							| 45 | 44 | adantl |  |-  ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ z e. D ) /\ x = ( C +o z ) ) -> ( F ` x ) = ( F ` ( C +o z ) ) ) | 
						
							| 46 | 43 45 | eqtr4d |  |-  ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ z e. D ) /\ x = ( C +o z ) ) -> ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) = ( F ` x ) ) | 
						
							| 47 | 46 | eqeq2d |  |-  ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ z e. D ) /\ x = ( C +o z ) ) -> ( y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) <-> y = ( F ` x ) ) ) | 
						
							| 48 | 47 | biimpd |  |-  ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ z e. D ) /\ x = ( C +o z ) ) -> ( y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) -> y = ( F ` x ) ) ) | 
						
							| 49 | 48 | expimpd |  |-  ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ z e. D ) -> ( ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) -> y = ( F ` x ) ) ) | 
						
							| 50 | 49 | rexlimdva |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) -> ( E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) -> y = ( F ` x ) ) ) | 
						
							| 51 |  | simplr |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) -> ( C e. On /\ D e. On ) ) | 
						
							| 52 |  | eloni |  |-  ( ( C +o D ) e. On -> Ord ( C +o D ) ) | 
						
							| 53 | 7 52 | syl |  |-  ( ( C e. On /\ D e. On ) -> Ord ( C +o D ) ) | 
						
							| 54 |  | eloni |  |-  ( C e. On -> Ord C ) | 
						
							| 55 | 54 | adantr |  |-  ( ( C e. On /\ D e. On ) -> Ord C ) | 
						
							| 56 |  | ordeldif |  |-  ( ( Ord ( C +o D ) /\ Ord C ) -> ( x e. ( ( C +o D ) \ C ) <-> ( x e. ( C +o D ) /\ C C_ x ) ) ) | 
						
							| 57 | 53 55 56 | syl2anc |  |-  ( ( C e. On /\ D e. On ) -> ( x e. ( ( C +o D ) \ C ) <-> ( x e. ( C +o D ) /\ C C_ x ) ) ) | 
						
							| 58 | 57 | adantl |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( x e. ( ( C +o D ) \ C ) <-> ( x e. ( C +o D ) /\ C C_ x ) ) ) | 
						
							| 59 | 58 | biimpa |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) -> ( x e. ( C +o D ) /\ C C_ x ) ) | 
						
							| 60 | 59 | ancomd |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) -> ( C C_ x /\ x e. ( C +o D ) ) ) | 
						
							| 61 | 51 60 | jca |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) -> ( ( C e. On /\ D e. On ) /\ ( C C_ x /\ x e. ( C +o D ) ) ) ) | 
						
							| 62 | 61 | adantr |  |-  ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) -> ( ( C e. On /\ D e. On ) /\ ( C C_ x /\ x e. ( C +o D ) ) ) ) | 
						
							| 63 |  | oawordex2 |  |-  ( ( ( C e. On /\ D e. On ) /\ ( C C_ x /\ x e. ( C +o D ) ) ) -> E. z e. D ( C +o z ) = x ) | 
						
							| 64 | 62 63 | syl |  |-  ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) -> E. z e. D ( C +o z ) = x ) | 
						
							| 65 |  | simpr |  |-  ( ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) /\ z e. D ) /\ ( C +o z ) = x ) -> ( C +o z ) = x ) | 
						
							| 66 | 65 | eqcomd |  |-  ( ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) /\ z e. D ) /\ ( C +o z ) = x ) -> x = ( C +o z ) ) | 
						
							| 67 | 65 | fveq2d |  |-  ( ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) /\ z e. D ) /\ ( C +o z ) = x ) -> ( F ` ( C +o z ) ) = ( F ` x ) ) | 
						
							| 68 | 42 | ad2antlr |  |-  ( ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) /\ z e. D ) /\ ( C +o z ) = x ) -> ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) = ( F ` ( C +o z ) ) ) | 
						
							| 69 |  | simpllr |  |-  ( ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) /\ z e. D ) /\ ( C +o z ) = x ) -> y = ( F ` x ) ) | 
						
							| 70 | 67 68 69 | 3eqtr4rd |  |-  ( ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) /\ z e. D ) /\ ( C +o z ) = x ) -> y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) | 
						
							| 71 | 66 70 | jca |  |-  ( ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) /\ z e. D ) /\ ( C +o z ) = x ) -> ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) | 
						
							| 72 | 71 | ex |  |-  ( ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) /\ z e. D ) -> ( ( C +o z ) = x -> ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) ) | 
						
							| 73 | 72 | reximdva |  |-  ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) -> ( E. z e. D ( C +o z ) = x -> E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) ) | 
						
							| 74 | 64 73 | mpd |  |-  ( ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) /\ y = ( F ` x ) ) -> E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) | 
						
							| 75 | 74 | ex |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) -> ( y = ( F ` x ) -> E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) ) | 
						
							| 76 | 50 75 | impbid |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) -> ( E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) <-> y = ( F ` x ) ) ) | 
						
							| 77 |  | eldifi |  |-  ( x e. ( ( C +o D ) \ C ) -> x e. ( C +o D ) ) | 
						
							| 78 |  | eqcom |  |-  ( y = ( F ` x ) <-> ( F ` x ) = y ) | 
						
							| 79 |  | fnbrfvb |  |-  ( ( F Fn ( C +o D ) /\ x e. ( C +o D ) ) -> ( ( F ` x ) = y <-> x F y ) ) | 
						
							| 80 | 78 79 | bitrid |  |-  ( ( F Fn ( C +o D ) /\ x e. ( C +o D ) ) -> ( y = ( F ` x ) <-> x F y ) ) | 
						
							| 81 | 20 77 80 | syl2an |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) -> ( y = ( F ` x ) <-> x F y ) ) | 
						
							| 82 | 76 81 | bitrd |  |-  ( ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) /\ x e. ( ( C +o D ) \ C ) ) -> ( E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) <-> x F y ) ) | 
						
							| 83 | 82 | pm5.32da |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( ( x e. ( ( C +o D ) \ C ) /\ E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) <-> ( x e. ( ( C +o D ) \ C ) /\ x F y ) ) ) | 
						
							| 84 | 83 | opabbidv |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> { <. x , y >. | ( x e. ( ( C +o D ) \ C ) /\ E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) } = { <. x , y >. | ( x e. ( ( C +o D ) \ C ) /\ x F y ) } ) | 
						
							| 85 |  | dfres2 |  |-  ( F |` ( ( C +o D ) \ C ) ) = { <. x , y >. | ( x e. ( ( C +o D ) \ C ) /\ x F y ) } | 
						
							| 86 | 84 85 | eqtr4di |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> { <. x , y >. | ( x e. ( ( C +o D ) \ C ) /\ E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) } = ( F |` ( ( C +o D ) \ C ) ) ) | 
						
							| 87 | 86 | uneq2d |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( ( F |` C ) u. { <. x , y >. | ( x e. ( ( C +o D ) \ C ) /\ E. z e. D ( x = ( C +o z ) /\ y = ( ( d e. D |-> ( F ` ( C +o d ) ) ) ` z ) ) ) } ) = ( ( F |` C ) u. ( F |` ( ( C +o D ) \ C ) ) ) ) | 
						
							| 88 | 38 87 | eqtrd |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( ( F |` C ) .+ ( d e. D |-> ( F ` ( C +o d ) ) ) ) = ( ( F |` C ) u. ( F |` ( ( C +o D ) \ C ) ) ) ) | 
						
							| 89 |  | resundi |  |-  ( F |` ( C u. ( ( C +o D ) \ C ) ) ) = ( ( F |` C ) u. ( F |` ( ( C +o D ) \ C ) ) ) | 
						
							| 90 | 89 | a1i |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( F |` ( C u. ( ( C +o D ) \ C ) ) ) = ( ( F |` C ) u. ( F |` ( ( C +o D ) \ C ) ) ) ) | 
						
							| 91 |  | undif |  |-  ( C C_ ( C +o D ) <-> ( C u. ( ( C +o D ) \ C ) ) = ( C +o D ) ) | 
						
							| 92 | 16 91 | sylib |  |-  ( ( C e. On /\ D e. On ) -> ( C u. ( ( C +o D ) \ C ) ) = ( C +o D ) ) | 
						
							| 93 | 92 | adantl |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( C u. ( ( C +o D ) \ C ) ) = ( C +o D ) ) | 
						
							| 94 | 93 | reseq2d |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( F |` ( C u. ( ( C +o D ) \ C ) ) ) = ( F |` ( C +o D ) ) ) | 
						
							| 95 |  | fnresdm |  |-  ( F Fn ( C +o D ) -> ( F |` ( C +o D ) ) = F ) | 
						
							| 96 | 95 | adantr |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( F |` ( C +o D ) ) = F ) | 
						
							| 97 | 94 96 | eqtrd |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( F |` ( C u. ( ( C +o D ) \ C ) ) ) = F ) | 
						
							| 98 | 88 90 97 | 3eqtr2d |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( ( F |` C ) .+ ( d e. D |-> ( F ` ( C +o d ) ) ) ) = F ) | 
						
							| 99 |  | dmres |  |-  dom ( F |` C ) = ( C i^i dom F ) | 
						
							| 100 | 17 6 | sseqtrrd |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> C C_ dom F ) | 
						
							| 101 |  | dfss2 |  |-  ( C C_ dom F <-> ( C i^i dom F ) = C ) | 
						
							| 102 | 100 101 | sylib |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> ( C i^i dom F ) = C ) | 
						
							| 103 | 99 102 | eqtrid |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> dom ( F |` C ) = C ) | 
						
							| 104 | 32 33 | dmmpti |  |-  dom ( d e. D |-> ( F ` ( C +o d ) ) ) = D | 
						
							| 105 | 104 | a1i |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> dom ( d e. D |-> ( F ` ( C +o d ) ) ) = D ) | 
						
							| 106 |  | oveq1 |  |-  ( u = ( F |` C ) -> ( u .+ v ) = ( ( F |` C ) .+ v ) ) | 
						
							| 107 | 106 | eqeq1d |  |-  ( u = ( F |` C ) -> ( ( u .+ v ) = F <-> ( ( F |` C ) .+ v ) = F ) ) | 
						
							| 108 |  | dmeq |  |-  ( u = ( F |` C ) -> dom u = dom ( F |` C ) ) | 
						
							| 109 | 108 | eqeq1d |  |-  ( u = ( F |` C ) -> ( dom u = C <-> dom ( F |` C ) = C ) ) | 
						
							| 110 | 107 109 | 3anbi12d |  |-  ( u = ( F |` C ) -> ( ( ( u .+ v ) = F /\ dom u = C /\ dom v = D ) <-> ( ( ( F |` C ) .+ v ) = F /\ dom ( F |` C ) = C /\ dom v = D ) ) ) | 
						
							| 111 |  | oveq2 |  |-  ( v = ( d e. D |-> ( F ` ( C +o d ) ) ) -> ( ( F |` C ) .+ v ) = ( ( F |` C ) .+ ( d e. D |-> ( F ` ( C +o d ) ) ) ) ) | 
						
							| 112 | 111 | eqeq1d |  |-  ( v = ( d e. D |-> ( F ` ( C +o d ) ) ) -> ( ( ( F |` C ) .+ v ) = F <-> ( ( F |` C ) .+ ( d e. D |-> ( F ` ( C +o d ) ) ) ) = F ) ) | 
						
							| 113 |  | dmeq |  |-  ( v = ( d e. D |-> ( F ` ( C +o d ) ) ) -> dom v = dom ( d e. D |-> ( F ` ( C +o d ) ) ) ) | 
						
							| 114 | 113 | eqeq1d |  |-  ( v = ( d e. D |-> ( F ` ( C +o d ) ) ) -> ( dom v = D <-> dom ( d e. D |-> ( F ` ( C +o d ) ) ) = D ) ) | 
						
							| 115 | 112 114 | 3anbi13d |  |-  ( v = ( d e. D |-> ( F ` ( C +o d ) ) ) -> ( ( ( ( F |` C ) .+ v ) = F /\ dom ( F |` C ) = C /\ dom v = D ) <-> ( ( ( F |` C ) .+ ( d e. D |-> ( F ` ( C +o d ) ) ) ) = F /\ dom ( F |` C ) = C /\ dom ( d e. D |-> ( F ` ( C +o d ) ) ) = D ) ) ) | 
						
							| 116 | 110 115 | rspc2ev |  |-  ( ( ( F |` C ) e. ( ran F ^m C ) /\ ( d e. D |-> ( F ` ( C +o d ) ) ) e. ( ran F ^m D ) /\ ( ( ( F |` C ) .+ ( d e. D |-> ( F ` ( C +o d ) ) ) ) = F /\ dom ( F |` C ) = C /\ dom ( d e. D |-> ( F ` ( C +o d ) ) ) = D ) ) -> E. u e. ( ran F ^m C ) E. v e. ( ran F ^m D ) ( ( u .+ v ) = F /\ dom u = C /\ dom v = D ) ) | 
						
							| 117 | 19 30 98 103 105 116 | syl113anc |  |-  ( ( F Fn ( C +o D ) /\ ( C e. On /\ D e. On ) ) -> E. u e. ( ran F ^m C ) E. v e. ( ran F ^m D ) ( ( u .+ v ) = F /\ dom u = C /\ dom v = D ) ) |