Theorem f1dmvrnfibi 6921

Description: A one-to-one function whose domain is a set is finite if and only if its range is finite. See also f1vrnfibi 6922. (Contributed by AV, 10-Jan-2020.)

Assertion

Ref	Expression
f1dmvrnfibi	|- ( ( A e. V /\ F : A -1-1-> B ) -> ( F e. Fin <-> ran F e. Fin ) )

Proof of Theorem f1dmvrnfibi

Step	Hyp	Ref	Expression
1		f1rel 5407	. . . 4 |- ( F : A -1-1-> B -> Rel F )
2	1	ad2antlr 486	. . 3 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ F e. Fin ) -> Rel F )
3		f1cnv 5466	. . . . 5 |- ( F : A -1-1-> B -> `' F : ran F -1-1-onto-> A )
4		f1ofun 5444	. . . . 5 |- ( `' F : ran F -1-1-onto-> A -> Fun `' F )
5	3, 4	syl 14	. . . 4 |- ( F : A -1-1-> B -> Fun `' F )
6	5	ad2antlr 486	. . 3 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ F e. Fin ) -> Fun `' F )
7		simpr 109	. . 3 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ F e. Fin ) -> F e. Fin )
8		funrnfi 6919	. . 3 |- ( ( Rel F /\ Fun `' F /\ F e. Fin ) -> ran F e. Fin )
9	2, 6, 7, 8	syl3anc 1233	. 2 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ F e. Fin ) -> ran F e. Fin )
10		simpr 109	. . . 4 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ ran F e. Fin ) -> ran F e. Fin )
11		f1dm 5408	. . . . . . . 8 |- ( F : A -1-1-> B -> dom F = A )
12		f1f1orn 5453	. . . . . . . 8 |- ( F : A -1-1-> B -> F : A -1-1-onto-> ran F )
13		eleq1 2233	. . . . . . . . . . . 12 |- ( A = dom F -> ( A e. V <-> dom F e. V ) )
14		f1oeq2 5432	. . . . . . . . . . . 12 |- ( A = dom F -> ( F : A -1-1-onto-> ran F <-> F : dom F -1-1-onto-> ran F ) )
15	13, 14	anbi12d 470	. . . . . . . . . . 11 |- ( A = dom F -> ( ( A e. V /\ F : A -1-1-onto-> ran F ) <-> ( dom F e. V /\ F : dom F -1-1-onto-> ran F ) ) )
16	15	eqcoms 2173	. . . . . . . . . 10 |- ( dom F = A -> ( ( A e. V /\ F : A -1-1-onto-> ran F ) <-> ( dom F e. V /\ F : dom F -1-1-onto-> ran F ) ) )
17	16	biimpd 143	. . . . . . . . 9 |- ( dom F = A -> ( ( A e. V /\ F : A -1-1-onto-> ran F ) -> ( dom F e. V /\ F : dom F -1-1-onto-> ran F ) ) )
18	17	expcomd 1434	. . . . . . . 8 |- ( dom F = A -> ( F : A -1-1-onto-> ran F -> ( A e. V -> ( dom F e. V /\ F : dom F -1-1-onto-> ran F ) ) ) )
19	11, 12, 18	sylc 62	. . . . . . 7 |- ( F : A -1-1-> B -> ( A e. V -> ( dom F e. V /\ F : dom F -1-1-onto-> ran F ) ) )
20	19	impcom 124	. . . . . 6 |- ( ( A e. V /\ F : A -1-1-> B ) -> ( dom F e. V /\ F : dom F -1-1-onto-> ran F ) )
21	20	adantr 274	. . . . 5 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ ran F e. Fin ) -> ( dom F e. V /\ F : dom F -1-1-onto-> ran F ) )
22		f1oeng 6735	. . . . 5 |- ( ( dom F e. V /\ F : dom F -1-1-onto-> ran F ) -> dom F ~~ ran F )
23	21, 22	syl 14	. . . 4 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ ran F e. Fin ) -> dom F ~~ ran F )
24		enfii 6852	. . . 4 |- ( ( ran F e. Fin /\ dom F ~~ ran F ) -> dom F e. Fin )
25	10, 23, 24	syl2anc 409	. . 3 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ ran F e. Fin ) -> dom F e. Fin )
26		f1fun 5406	. . . . 5 |- ( F : A -1-1-> B -> Fun F )
27	26	ad2antlr 486	. . . 4 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ ran F e. Fin ) -> Fun F )
28		fundmfibi 6916	. . . 4 |- ( Fun F -> ( F e. Fin <-> dom F e. Fin ) )
29	27, 28	syl 14	. . 3 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ ran F e. Fin ) -> ( F e. Fin <-> dom F e. Fin ) )
30	25, 29	mpbird 166	. 2 |- ( ( ( A e. V /\ F : A -1-1-> B ) /\ ran F e. Fin ) -> F e. Fin )
31	9, 30	impbida 591	1 |- ( ( A e. V /\ F : A -1-1-> B ) -> ( F e. Fin <-> ran F e. Fin ) )

Syntax hints:   -> wi 4   /\ wa 103   <-> wb 104   = wceq 1348   e. wcel 2141   class class class wbr 3989   `'ccnv 4610   dom cdm 4611   ran crn 4612   Rel wrel 4616   Fun wfun 5192   -1-1->wf1 5195   -1-1-onto->wf1o 5197   ~~ cen 6716   Fincfn 6718

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 609  ax-in2 610  ax-io 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528  ax-13 2143  ax-14 2144  ax-ext 2152  ax-coll 4104  ax-sep 4107  ax-nul 4115  ax-pow 4160  ax-pr 4194  ax-un 4418  ax-setind 4521  ax-iinf 4572

This theorem depends on definitions:  df-bi 116  df-dc 830  df-3or 974  df-3an 975  df-tru 1351  df-fal 1354  df-nf 1454  df-sb 1756  df-eu 2022  df-mo 2023  df-clab 2157  df-cleq 2163  df-clel 2166  df-nfc 2301  df-ne 2341  df-ral 2453  df-rex 2454  df-reu 2455  df-rab 2457  df-v 2732  df-sbc 2956  df-csb 3050  df-dif 3123  df-un 3125  df-in 3127  df-ss 3134  df-nul 3415  df-if 3527  df-pw 3568  df-sn 3589  df-pr 3590  df-op 3592  df-uni 3797  df-int 3832  df-iun 3875  df-br 3990  df-opab 4051  df-mpt 4052  df-tr 4088  df-id 4278  df-iord 4351  df-on 4353  df-suc 4356  df-iom 4575  df-xp 4617  df-rel 4618  df-cnv 4619  df-co 4620  df-dm 4621  df-rn 4622  df-res 4623  df-ima 4624  df-iota 5160  df-fun 5200  df-fn 5201  df-f 5202  df-f1 5203  df-fo 5204  df-f1o 5205  df-fv 5206  df-1st 6119  df-2nd 6120  df-1o 6395  df-er 6513  df-en 6719  df-fin 6721

This theorem is referenced by:  f1vrnfibi  6922