Metamath Proof Explorer


Theorem climfveqf

Description: Two functions that are eventually equal to one another have the same limit. (Contributed by Glauco Siliprandi, 23-Oct-2021)

Ref Expression
Hypotheses climfveqf.p
|- F/ k ph
climfveqf.n
|- F/_ k F
climfveqf.o
|- F/_ k G
climfveqf.z
|- Z = ( ZZ>= ` M )
climfveqf.f
|- ( ph -> F e. V )
climfveqf.g
|- ( ph -> G e. W )
climfveqf.m
|- ( ph -> M e. ZZ )
climfveqf.e
|- ( ( ph /\ k e. Z ) -> ( F ` k ) = ( G ` k ) )
Assertion climfveqf
|- ( ph -> ( ~~> ` F ) = ( ~~> ` G ) )

Proof

Step Hyp Ref Expression
1 climfveqf.p
 |-  F/ k ph
2 climfveqf.n
 |-  F/_ k F
3 climfveqf.o
 |-  F/_ k G
4 climfveqf.z
 |-  Z = ( ZZ>= ` M )
5 climfveqf.f
 |-  ( ph -> F e. V )
6 climfveqf.g
 |-  ( ph -> G e. W )
7 climfveqf.m
 |-  ( ph -> M e. ZZ )
8 climfveqf.e
 |-  ( ( ph /\ k e. Z ) -> ( F ` k ) = ( G ` k ) )
9 climdm
 |-  ( F e. dom ~~> <-> F ~~> ( ~~> ` F ) )
10 9 biimpi
 |-  ( F e. dom ~~> -> F ~~> ( ~~> ` F ) )
11 10 adantl
 |-  ( ( ph /\ F e. dom ~~> ) -> F ~~> ( ~~> ` F ) )
12 11 9 sylibr
 |-  ( ( ph /\ F e. dom ~~> ) -> F e. dom ~~> )
13 nfcv
 |-  F/_ k j
14 13 nfel1
 |-  F/ k j e. Z
15 1 14 nfan
 |-  F/ k ( ph /\ j e. Z )
16 2 13 nffv
 |-  F/_ k ( F ` j )
17 3 13 nffv
 |-  F/_ k ( G ` j )
18 16 17 nfeq
 |-  F/ k ( F ` j ) = ( G ` j )
19 15 18 nfim
 |-  F/ k ( ( ph /\ j e. Z ) -> ( F ` j ) = ( G ` j ) )
20 eleq1w
 |-  ( k = j -> ( k e. Z <-> j e. Z ) )
21 20 anbi2d
 |-  ( k = j -> ( ( ph /\ k e. Z ) <-> ( ph /\ j e. Z ) ) )
22 fveq2
 |-  ( k = j -> ( F ` k ) = ( F ` j ) )
23 fveq2
 |-  ( k = j -> ( G ` k ) = ( G ` j ) )
24 22 23 eqeq12d
 |-  ( k = j -> ( ( F ` k ) = ( G ` k ) <-> ( F ` j ) = ( G ` j ) ) )
25 21 24 imbi12d
 |-  ( k = j -> ( ( ( ph /\ k e. Z ) -> ( F ` k ) = ( G ` k ) ) <-> ( ( ph /\ j e. Z ) -> ( F ` j ) = ( G ` j ) ) ) )
26 19 25 8 chvarfv
 |-  ( ( ph /\ j e. Z ) -> ( F ` j ) = ( G ` j ) )
27 4 5 6 7 26 climeldmeq
 |-  ( ph -> ( F e. dom ~~> <-> G e. dom ~~> ) )
28 27 adantr
 |-  ( ( ph /\ F e. dom ~~> ) -> ( F e. dom ~~> <-> G e. dom ~~> ) )
29 12 28 mpbid
 |-  ( ( ph /\ F e. dom ~~> ) -> G e. dom ~~> )
30 climdm
 |-  ( G e. dom ~~> <-> G ~~> ( ~~> ` G ) )
31 29 30 sylib
 |-  ( ( ph /\ F e. dom ~~> ) -> G ~~> ( ~~> ` G ) )
32 6 adantr
 |-  ( ( ph /\ F e. dom ~~> ) -> G e. W )
33 5 adantr
 |-  ( ( ph /\ F e. dom ~~> ) -> F e. V )
34 7 adantr
 |-  ( ( ph /\ F e. dom ~~> ) -> M e. ZZ )
35 26 eqcomd
 |-  ( ( ph /\ j e. Z ) -> ( G ` j ) = ( F ` j ) )
36 35 adantlr
 |-  ( ( ( ph /\ F e. dom ~~> ) /\ j e. Z ) -> ( G ` j ) = ( F ` j ) )
37 4 32 33 34 36 climeq
 |-  ( ( ph /\ F e. dom ~~> ) -> ( G ~~> ( ~~> ` G ) <-> F ~~> ( ~~> ` G ) ) )
38 31 37 mpbid
 |-  ( ( ph /\ F e. dom ~~> ) -> F ~~> ( ~~> ` G ) )
39 climuni
 |-  ( ( F ~~> ( ~~> ` F ) /\ F ~~> ( ~~> ` G ) ) -> ( ~~> ` F ) = ( ~~> ` G ) )
40 11 38 39 syl2anc
 |-  ( ( ph /\ F e. dom ~~> ) -> ( ~~> ` F ) = ( ~~> ` G ) )
41 ndmfv
 |-  ( -. F e. dom ~~> -> ( ~~> ` F ) = (/) )
42 41 adantl
 |-  ( ( ph /\ -. F e. dom ~~> ) -> ( ~~> ` F ) = (/) )
43 simpr
 |-  ( ( ph /\ -. F e. dom ~~> ) -> -. F e. dom ~~> )
44 27 adantr
 |-  ( ( ph /\ -. F e. dom ~~> ) -> ( F e. dom ~~> <-> G e. dom ~~> ) )
45 43 44 mtbid
 |-  ( ( ph /\ -. F e. dom ~~> ) -> -. G e. dom ~~> )
46 ndmfv
 |-  ( -. G e. dom ~~> -> ( ~~> ` G ) = (/) )
47 45 46 syl
 |-  ( ( ph /\ -. F e. dom ~~> ) -> ( ~~> ` G ) = (/) )
48 42 47 eqtr4d
 |-  ( ( ph /\ -. F e. dom ~~> ) -> ( ~~> ` F ) = ( ~~> ` G ) )
49 40 48 pm2.61dan
 |-  ( ph -> ( ~~> ` F ) = ( ~~> ` G ) )