Metamath Proof Explorer


Theorem climeldmeqf

Description: Two functions that are eventually equal, either both are convergent or both are divergent. (Contributed by Glauco Siliprandi, 23-Oct-2021)

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

Proof

Step Hyp Ref Expression
1 climeldmeqf.p
 |-  F/ k ph
2 climeldmeqf.n
 |-  F/_ k F
3 climeldmeqf.o
 |-  F/_ k G
4 climeldmeqf.z
 |-  Z = ( ZZ>= ` M )
5 climeldmeqf.f
 |-  ( ph -> F e. V )
6 climeldmeqf.g
 |-  ( ph -> G e. W )
7 climeldmeqf.m
 |-  ( ph -> M e. ZZ )
8 climeldmeqf.e
 |-  ( ( ph /\ k e. Z ) -> ( F ` k ) = ( G ` k ) )
9 nfv
 |-  F/ k j e. Z
10 1 9 nfan
 |-  F/ k ( ph /\ j e. Z )
11 nfcv
 |-  F/_ k j
12 2 11 nffv
 |-  F/_ k ( F ` j )
13 3 11 nffv
 |-  F/_ k ( G ` j )
14 12 13 nfeq
 |-  F/ k ( F ` j ) = ( G ` j )
15 10 14 nfim
 |-  F/ k ( ( ph /\ j e. Z ) -> ( F ` j ) = ( G ` j ) )
16 eleq1w
 |-  ( k = j -> ( k e. Z <-> j e. Z ) )
17 16 anbi2d
 |-  ( k = j -> ( ( ph /\ k e. Z ) <-> ( ph /\ j e. Z ) ) )
18 fveq2
 |-  ( k = j -> ( F ` k ) = ( F ` j ) )
19 fveq2
 |-  ( k = j -> ( G ` k ) = ( G ` j ) )
20 18 19 eqeq12d
 |-  ( k = j -> ( ( F ` k ) = ( G ` k ) <-> ( F ` j ) = ( G ` j ) ) )
21 17 20 imbi12d
 |-  ( k = j -> ( ( ( ph /\ k e. Z ) -> ( F ` k ) = ( G ` k ) ) <-> ( ( ph /\ j e. Z ) -> ( F ` j ) = ( G ` j ) ) ) )
22 15 21 8 chvarfv
 |-  ( ( ph /\ j e. Z ) -> ( F ` j ) = ( G ` j ) )
23 4 5 6 7 22 climeldmeq
 |-  ( ph -> ( F e. dom ~~> <-> G e. dom ~~> ) )