Metamath Proof Explorer


Theorem lo1eq

Description: Two functions that are eventually equal to one another are eventually bounded if one of them is. (Contributed by Mario Carneiro, 26-May-2016)

Ref Expression
Hypotheses lo1eq.1 ( ( 𝜑𝑥𝐴 ) → 𝐵 ∈ ℝ )
lo1eq.2 ( ( 𝜑𝑥𝐴 ) → 𝐶 ∈ ℝ )
lo1eq.3 ( 𝜑𝐷 ∈ ℝ )
lo1eq.4 ( ( 𝜑 ∧ ( 𝑥𝐴𝐷𝑥 ) ) → 𝐵 = 𝐶 )
Assertion lo1eq ( 𝜑 → ( ( 𝑥𝐴𝐵 ) ∈ ≤𝑂(1) ↔ ( 𝑥𝐴𝐶 ) ∈ ≤𝑂(1) ) )

Proof

Step Hyp Ref Expression
1 lo1eq.1 ( ( 𝜑𝑥𝐴 ) → 𝐵 ∈ ℝ )
2 lo1eq.2 ( ( 𝜑𝑥𝐴 ) → 𝐶 ∈ ℝ )
3 lo1eq.3 ( 𝜑𝐷 ∈ ℝ )
4 lo1eq.4 ( ( 𝜑 ∧ ( 𝑥𝐴𝐷𝑥 ) ) → 𝐵 = 𝐶 )
5 lo1dm ( ( 𝑥𝐴𝐵 ) ∈ ≤𝑂(1) → dom ( 𝑥𝐴𝐵 ) ⊆ ℝ )
6 eqid ( 𝑥𝐴𝐵 ) = ( 𝑥𝐴𝐵 )
7 6 1 dmmptd ( 𝜑 → dom ( 𝑥𝐴𝐵 ) = 𝐴 )
8 7 sseq1d ( 𝜑 → ( dom ( 𝑥𝐴𝐵 ) ⊆ ℝ ↔ 𝐴 ⊆ ℝ ) )
9 5 8 imbitrid ( 𝜑 → ( ( 𝑥𝐴𝐵 ) ∈ ≤𝑂(1) → 𝐴 ⊆ ℝ ) )
10 lo1dm ( ( 𝑥𝐴𝐶 ) ∈ ≤𝑂(1) → dom ( 𝑥𝐴𝐶 ) ⊆ ℝ )
11 eqid ( 𝑥𝐴𝐶 ) = ( 𝑥𝐴𝐶 )
12 11 2 dmmptd ( 𝜑 → dom ( 𝑥𝐴𝐶 ) = 𝐴 )
13 12 sseq1d ( 𝜑 → ( dom ( 𝑥𝐴𝐶 ) ⊆ ℝ ↔ 𝐴 ⊆ ℝ ) )
14 10 13 imbitrid ( 𝜑 → ( ( 𝑥𝐴𝐶 ) ∈ ≤𝑂(1) → 𝐴 ⊆ ℝ ) )
15 elin ( 𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ↔ ( 𝑥𝐴𝑥 ∈ ( 𝐷 [,) +∞ ) ) )
16 15 bilani ( ( 𝜑𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) → ( 𝑥𝐴𝑥 ∈ ( 𝐷 [,) +∞ ) ) )
17 16 simpld ( ( 𝜑𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) → 𝑥𝐴 )
18 16 simprd ( ( 𝜑𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) → 𝑥 ∈ ( 𝐷 [,) +∞ ) )
19 elicopnf ( 𝐷 ∈ ℝ → ( 𝑥 ∈ ( 𝐷 [,) +∞ ) ↔ ( 𝑥 ∈ ℝ ∧ 𝐷𝑥 ) ) )
20 3 19 syl ( 𝜑 → ( 𝑥 ∈ ( 𝐷 [,) +∞ ) ↔ ( 𝑥 ∈ ℝ ∧ 𝐷𝑥 ) ) )
21 20 biimpa ( ( 𝜑𝑥 ∈ ( 𝐷 [,) +∞ ) ) → ( 𝑥 ∈ ℝ ∧ 𝐷𝑥 ) )
22 18 21 syldan ( ( 𝜑𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) → ( 𝑥 ∈ ℝ ∧ 𝐷𝑥 ) )
23 22 simprd ( ( 𝜑𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) → 𝐷𝑥 )
24 17 23 jca ( ( 𝜑𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) → ( 𝑥𝐴𝐷𝑥 ) )
25 24 4 syldan ( ( 𝜑𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) → 𝐵 = 𝐶 )
26 25 mpteq2dva ( 𝜑 → ( 𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ↦ 𝐵 ) = ( 𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ↦ 𝐶 ) )
27 inss1 ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ⊆ 𝐴
28 resmpt ( ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ⊆ 𝐴 → ( ( 𝑥𝐴𝐵 ) ↾ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) = ( 𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ↦ 𝐵 ) )
29 27 28 ax-mp ( ( 𝑥𝐴𝐵 ) ↾ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) = ( 𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ↦ 𝐵 )
30 resmpt ( ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ⊆ 𝐴 → ( ( 𝑥𝐴𝐶 ) ↾ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) = ( 𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ↦ 𝐶 ) )
31 27 30 ax-mp ( ( 𝑥𝐴𝐶 ) ↾ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) = ( 𝑥 ∈ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ↦ 𝐶 )
32 26 29 31 3eqtr4g ( 𝜑 → ( ( 𝑥𝐴𝐵 ) ↾ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) = ( ( 𝑥𝐴𝐶 ) ↾ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) ) )
33 resres ( ( ( 𝑥𝐴𝐵 ) ↾ 𝐴 ) ↾ ( 𝐷 [,) +∞ ) ) = ( ( 𝑥𝐴𝐵 ) ↾ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) )
34 resres ( ( ( 𝑥𝐴𝐶 ) ↾ 𝐴 ) ↾ ( 𝐷 [,) +∞ ) ) = ( ( 𝑥𝐴𝐶 ) ↾ ( 𝐴 ∩ ( 𝐷 [,) +∞ ) ) )
35 32 33 34 3eqtr4g ( 𝜑 → ( ( ( 𝑥𝐴𝐵 ) ↾ 𝐴 ) ↾ ( 𝐷 [,) +∞ ) ) = ( ( ( 𝑥𝐴𝐶 ) ↾ 𝐴 ) ↾ ( 𝐷 [,) +∞ ) ) )
36 ssid 𝐴𝐴
37 resmpt ( 𝐴𝐴 → ( ( 𝑥𝐴𝐵 ) ↾ 𝐴 ) = ( 𝑥𝐴𝐵 ) )
38 reseq1 ( ( ( 𝑥𝐴𝐵 ) ↾ 𝐴 ) = ( 𝑥𝐴𝐵 ) → ( ( ( 𝑥𝐴𝐵 ) ↾ 𝐴 ) ↾ ( 𝐷 [,) +∞ ) ) = ( ( 𝑥𝐴𝐵 ) ↾ ( 𝐷 [,) +∞ ) ) )
39 36 37 38 mp2b ( ( ( 𝑥𝐴𝐵 ) ↾ 𝐴 ) ↾ ( 𝐷 [,) +∞ ) ) = ( ( 𝑥𝐴𝐵 ) ↾ ( 𝐷 [,) +∞ ) )
40 resmpt ( 𝐴𝐴 → ( ( 𝑥𝐴𝐶 ) ↾ 𝐴 ) = ( 𝑥𝐴𝐶 ) )
41 reseq1 ( ( ( 𝑥𝐴𝐶 ) ↾ 𝐴 ) = ( 𝑥𝐴𝐶 ) → ( ( ( 𝑥𝐴𝐶 ) ↾ 𝐴 ) ↾ ( 𝐷 [,) +∞ ) ) = ( ( 𝑥𝐴𝐶 ) ↾ ( 𝐷 [,) +∞ ) ) )
42 36 40 41 mp2b ( ( ( 𝑥𝐴𝐶 ) ↾ 𝐴 ) ↾ ( 𝐷 [,) +∞ ) ) = ( ( 𝑥𝐴𝐶 ) ↾ ( 𝐷 [,) +∞ ) )
43 35 39 42 3eqtr3g ( 𝜑 → ( ( 𝑥𝐴𝐵 ) ↾ ( 𝐷 [,) +∞ ) ) = ( ( 𝑥𝐴𝐶 ) ↾ ( 𝐷 [,) +∞ ) ) )
44 43 eleq1d ( 𝜑 → ( ( ( 𝑥𝐴𝐵 ) ↾ ( 𝐷 [,) +∞ ) ) ∈ ≤𝑂(1) ↔ ( ( 𝑥𝐴𝐶 ) ↾ ( 𝐷 [,) +∞ ) ) ∈ ≤𝑂(1) ) )
45 44 adantr ( ( 𝜑𝐴 ⊆ ℝ ) → ( ( ( 𝑥𝐴𝐵 ) ↾ ( 𝐷 [,) +∞ ) ) ∈ ≤𝑂(1) ↔ ( ( 𝑥𝐴𝐶 ) ↾ ( 𝐷 [,) +∞ ) ) ∈ ≤𝑂(1) ) )
46 1 fmpttd ( 𝜑 → ( 𝑥𝐴𝐵 ) : 𝐴 ⟶ ℝ )
47 46 adantr ( ( 𝜑𝐴 ⊆ ℝ ) → ( 𝑥𝐴𝐵 ) : 𝐴 ⟶ ℝ )
48 simpr ( ( 𝜑𝐴 ⊆ ℝ ) → 𝐴 ⊆ ℝ )
49 3 adantr ( ( 𝜑𝐴 ⊆ ℝ ) → 𝐷 ∈ ℝ )
50 47 48 49 lo1resb ( ( 𝜑𝐴 ⊆ ℝ ) → ( ( 𝑥𝐴𝐵 ) ∈ ≤𝑂(1) ↔ ( ( 𝑥𝐴𝐵 ) ↾ ( 𝐷 [,) +∞ ) ) ∈ ≤𝑂(1) ) )
51 2 fmpttd ( 𝜑 → ( 𝑥𝐴𝐶 ) : 𝐴 ⟶ ℝ )
52 51 adantr ( ( 𝜑𝐴 ⊆ ℝ ) → ( 𝑥𝐴𝐶 ) : 𝐴 ⟶ ℝ )
53 52 48 49 lo1resb ( ( 𝜑𝐴 ⊆ ℝ ) → ( ( 𝑥𝐴𝐶 ) ∈ ≤𝑂(1) ↔ ( ( 𝑥𝐴𝐶 ) ↾ ( 𝐷 [,) +∞ ) ) ∈ ≤𝑂(1) ) )
54 45 50 53 3bitr4d ( ( 𝜑𝐴 ⊆ ℝ ) → ( ( 𝑥𝐴𝐵 ) ∈ ≤𝑂(1) ↔ ( 𝑥𝐴𝐶 ) ∈ ≤𝑂(1) ) )
55 54 ex ( 𝜑 → ( 𝐴 ⊆ ℝ → ( ( 𝑥𝐴𝐵 ) ∈ ≤𝑂(1) ↔ ( 𝑥𝐴𝐶 ) ∈ ≤𝑂(1) ) ) )
56 9 14 55 pm5.21ndd ( 𝜑 → ( ( 𝑥𝐴𝐵 ) ∈ ≤𝑂(1) ↔ ( 𝑥𝐴𝐶 ) ∈ ≤𝑂(1) ) )