Metamath Proof Explorer


Theorem climfveq

Description: Two functions that are eventually equal to one another have the same limit. (Contributed by Glauco Siliprandi, 26-Jun-2021)

Ref Expression
Hypotheses climfveq.1 𝑍 = ( ℤ𝑀 )
climfveq.2 ( 𝜑𝐹𝑉 )
climfveq.3 ( 𝜑𝐺𝑊 )
climfveq.4 ( 𝜑𝑀 ∈ ℤ )
climfveq.5 ( ( 𝜑𝑘𝑍 ) → ( 𝐹𝑘 ) = ( 𝐺𝑘 ) )
Assertion climfveq ( 𝜑 → ( ⇝ ‘ 𝐹 ) = ( ⇝ ‘ 𝐺 ) )

Proof

Step Hyp Ref Expression
1 climfveq.1 𝑍 = ( ℤ𝑀 )
2 climfveq.2 ( 𝜑𝐹𝑉 )
3 climfveq.3 ( 𝜑𝐺𝑊 )
4 climfveq.4 ( 𝜑𝑀 ∈ ℤ )
5 climfveq.5 ( ( 𝜑𝑘𝑍 ) → ( 𝐹𝑘 ) = ( 𝐺𝑘 ) )
6 climdm ( 𝐹 ∈ dom ⇝ ↔ 𝐹 ⇝ ( ⇝ ‘ 𝐹 ) )
7 6 bilani ( ( 𝜑𝐹 ∈ dom ⇝ ) → 𝐹 ⇝ ( ⇝ ‘ 𝐹 ) )
8 7 6 sylibr ( ( 𝜑𝐹 ∈ dom ⇝ ) → 𝐹 ∈ dom ⇝ )
9 1 2 3 4 5 climeldmeq ( 𝜑 → ( 𝐹 ∈ dom ⇝ ↔ 𝐺 ∈ dom ⇝ ) )
10 9 adantr ( ( 𝜑𝐹 ∈ dom ⇝ ) → ( 𝐹 ∈ dom ⇝ ↔ 𝐺 ∈ dom ⇝ ) )
11 8 10 mpbid ( ( 𝜑𝐹 ∈ dom ⇝ ) → 𝐺 ∈ dom ⇝ )
12 climdm ( 𝐺 ∈ dom ⇝ ↔ 𝐺 ⇝ ( ⇝ ‘ 𝐺 ) )
13 11 12 sylib ( ( 𝜑𝐹 ∈ dom ⇝ ) → 𝐺 ⇝ ( ⇝ ‘ 𝐺 ) )
14 3 adantr ( ( 𝜑𝐹 ∈ dom ⇝ ) → 𝐺𝑊 )
15 2 adantr ( ( 𝜑𝐹 ∈ dom ⇝ ) → 𝐹𝑉 )
16 4 adantr ( ( 𝜑𝐹 ∈ dom ⇝ ) → 𝑀 ∈ ℤ )
17 5 eqcomd ( ( 𝜑𝑘𝑍 ) → ( 𝐺𝑘 ) = ( 𝐹𝑘 ) )
18 17 adantlr ( ( ( 𝜑𝐹 ∈ dom ⇝ ) ∧ 𝑘𝑍 ) → ( 𝐺𝑘 ) = ( 𝐹𝑘 ) )
19 1 14 15 16 18 climeq ( ( 𝜑𝐹 ∈ dom ⇝ ) → ( 𝐺 ⇝ ( ⇝ ‘ 𝐺 ) ↔ 𝐹 ⇝ ( ⇝ ‘ 𝐺 ) ) )
20 13 19 mpbid ( ( 𝜑𝐹 ∈ dom ⇝ ) → 𝐹 ⇝ ( ⇝ ‘ 𝐺 ) )
21 climuni ( ( 𝐹 ⇝ ( ⇝ ‘ 𝐹 ) ∧ 𝐹 ⇝ ( ⇝ ‘ 𝐺 ) ) → ( ⇝ ‘ 𝐹 ) = ( ⇝ ‘ 𝐺 ) )
22 7 20 21 syl2anc ( ( 𝜑𝐹 ∈ dom ⇝ ) → ( ⇝ ‘ 𝐹 ) = ( ⇝ ‘ 𝐺 ) )
23 ndmfv ( ¬ 𝐹 ∈ dom ⇝ → ( ⇝ ‘ 𝐹 ) = ∅ )
24 23 adantl ( ( 𝜑 ∧ ¬ 𝐹 ∈ dom ⇝ ) → ( ⇝ ‘ 𝐹 ) = ∅ )
25 simpr ( ( 𝜑 ∧ ¬ 𝐹 ∈ dom ⇝ ) → ¬ 𝐹 ∈ dom ⇝ )
26 9 adantr ( ( 𝜑 ∧ ¬ 𝐹 ∈ dom ⇝ ) → ( 𝐹 ∈ dom ⇝ ↔ 𝐺 ∈ dom ⇝ ) )
27 25 26 mtbid ( ( 𝜑 ∧ ¬ 𝐹 ∈ dom ⇝ ) → ¬ 𝐺 ∈ dom ⇝ )
28 ndmfv ( ¬ 𝐺 ∈ dom ⇝ → ( ⇝ ‘ 𝐺 ) = ∅ )
29 27 28 syl ( ( 𝜑 ∧ ¬ 𝐹 ∈ dom ⇝ ) → ( ⇝ ‘ 𝐺 ) = ∅ )
30 24 29 eqtr4d ( ( 𝜑 ∧ ¬ 𝐹 ∈ dom ⇝ ) → ( ⇝ ‘ 𝐹 ) = ( ⇝ ‘ 𝐺 ) )
31 22 30 pm2.61dan ( 𝜑 → ( ⇝ ‘ 𝐹 ) = ( ⇝ ‘ 𝐺 ) )