This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.

Metamath Proof Explorer


Theorem cncmpmax

Description: When the hypothesis for the extreme value theorem hold, then the sup of the range of the function belongs to the range, it is real and it an upper bound of the range. (Contributed by Glauco Siliprandi, 20-Apr-2017)

Ref Expression
Hypotheses cncmpmax.1 𝑇 = 𝐽
cncmpmax.2 𝐾 = ( topGen ‘ ran (,) )
cncmpmax.3 ( 𝜑𝐽 ∈ Comp )
cncmpmax.4 ( 𝜑𝐹 ∈ ( 𝐽 Cn 𝐾 ) )
cncmpmax.5 ( 𝜑𝑇 ≠ ∅ )
Assertion cncmpmax ( 𝜑 → ( sup ( ran 𝐹 , ℝ , < ) ∈ ran 𝐹 ∧ sup ( ran 𝐹 , ℝ , < ) ∈ ℝ ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ sup ( ran 𝐹 , ℝ , < ) ) )

Proof

Step Hyp Ref Expression
1 cncmpmax.1 𝑇 = 𝐽
2 cncmpmax.2 𝐾 = ( topGen ‘ ran (,) )
3 cncmpmax.3 ( 𝜑𝐽 ∈ Comp )
4 cncmpmax.4 ( 𝜑𝐹 ∈ ( 𝐽 Cn 𝐾 ) )
5 cncmpmax.5 ( 𝜑𝑇 ≠ ∅ )
6 1 2 3 4 5 evth ( 𝜑 → ∃ 𝑥𝑇𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) )
7 eqid ( 𝐽 Cn 𝐾 ) = ( 𝐽 Cn 𝐾 )
8 2 1 7 4 fcnre ( 𝜑𝐹 : 𝑇 ⟶ ℝ )
9 8 frnd ( 𝜑 → ran 𝐹 ⊆ ℝ )
10 9 adantr ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) → ran 𝐹 ⊆ ℝ )
11 8 ffund ( 𝜑 → Fun 𝐹 )
12 11 adantr ( ( 𝜑𝑥𝑇 ) → Fun 𝐹 )
13 simpr ( ( 𝜑𝑥𝑇 ) → 𝑥𝑇 )
14 8 adantr ( ( 𝜑𝑥𝑇 ) → 𝐹 : 𝑇 ⟶ ℝ )
15 14 fdmd ( ( 𝜑𝑥𝑇 ) → dom 𝐹 = 𝑇 )
16 13 15 eleqtrrd ( ( 𝜑𝑥𝑇 ) → 𝑥 ∈ dom 𝐹 )
17 fvelrn ( ( Fun 𝐹𝑥 ∈ dom 𝐹 ) → ( 𝐹𝑥 ) ∈ ran 𝐹 )
18 12 16 17 syl2anc ( ( 𝜑𝑥𝑇 ) → ( 𝐹𝑥 ) ∈ ran 𝐹 )
19 18 adantrr ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) → ( 𝐹𝑥 ) ∈ ran 𝐹 )
20 ffn ( 𝐹 : 𝑇 ⟶ ℝ → 𝐹 Fn 𝑇 )
21 fvelrnb ( 𝐹 Fn 𝑇 → ( 𝑦 ∈ ran 𝐹 ↔ ∃ 𝑠𝑇 ( 𝐹𝑠 ) = 𝑦 ) )
22 8 20 21 3syl ( 𝜑 → ( 𝑦 ∈ ran 𝐹 ↔ ∃ 𝑠𝑇 ( 𝐹𝑠 ) = 𝑦 ) )
23 22 biimpa ( ( 𝜑𝑦 ∈ ran 𝐹 ) → ∃ 𝑠𝑇 ( 𝐹𝑠 ) = 𝑦 )
24 df-rex ( ∃ 𝑠𝑇 ( 𝐹𝑠 ) = 𝑦 ↔ ∃ 𝑠 ( 𝑠𝑇 ∧ ( 𝐹𝑠 ) = 𝑦 ) )
25 23 24 sylib ( ( 𝜑𝑦 ∈ ran 𝐹 ) → ∃ 𝑠 ( 𝑠𝑇 ∧ ( 𝐹𝑠 ) = 𝑦 ) )
26 25 adantlr ( ( ( 𝜑 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ∧ 𝑦 ∈ ran 𝐹 ) → ∃ 𝑠 ( 𝑠𝑇 ∧ ( 𝐹𝑠 ) = 𝑦 ) )
27 simprr ( ( ( ( 𝜑 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ∧ 𝑦 ∈ ran 𝐹 ) ∧ ( 𝑠𝑇 ∧ ( 𝐹𝑠 ) = 𝑦 ) ) → ( 𝐹𝑠 ) = 𝑦 )
28 simpllr ( ( ( ( 𝜑 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ∧ 𝑦 ∈ ran 𝐹 ) ∧ ( 𝑠𝑇 ∧ ( 𝐹𝑠 ) = 𝑦 ) ) → ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) )
29 simprl ( ( ( ( 𝜑 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ∧ 𝑦 ∈ ran 𝐹 ) ∧ ( 𝑠𝑇 ∧ ( 𝐹𝑠 ) = 𝑦 ) ) → 𝑠𝑇 )
30 fveq2 ( 𝑡 = 𝑠 → ( 𝐹𝑡 ) = ( 𝐹𝑠 ) )
31 30 breq1d ( 𝑡 = 𝑠 → ( ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ↔ ( 𝐹𝑠 ) ≤ ( 𝐹𝑥 ) ) )
32 31 rspccva ( ( ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ∧ 𝑠𝑇 ) → ( 𝐹𝑠 ) ≤ ( 𝐹𝑥 ) )
33 28 29 32 syl2anc ( ( ( ( 𝜑 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ∧ 𝑦 ∈ ran 𝐹 ) ∧ ( 𝑠𝑇 ∧ ( 𝐹𝑠 ) = 𝑦 ) ) → ( 𝐹𝑠 ) ≤ ( 𝐹𝑥 ) )
34 27 33 eqbrtrrd ( ( ( ( 𝜑 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ∧ 𝑦 ∈ ran 𝐹 ) ∧ ( 𝑠𝑇 ∧ ( 𝐹𝑠 ) = 𝑦 ) ) → 𝑦 ≤ ( 𝐹𝑥 ) )
35 26 34 exlimddv ( ( ( 𝜑 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ∧ 𝑦 ∈ ran 𝐹 ) → 𝑦 ≤ ( 𝐹𝑥 ) )
36 35 ralrimiva ( ( 𝜑 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) → ∀ 𝑦 ∈ ran 𝐹 𝑦 ≤ ( 𝐹𝑥 ) )
37 36 adantrl ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) → ∀ 𝑦 ∈ ran 𝐹 𝑦 ≤ ( 𝐹𝑥 ) )
38 ubelsupr ( ( ran 𝐹 ⊆ ℝ ∧ ( 𝐹𝑥 ) ∈ ran 𝐹 ∧ ∀ 𝑦 ∈ ran 𝐹 𝑦 ≤ ( 𝐹𝑥 ) ) → ( 𝐹𝑥 ) = sup ( ran 𝐹 , ℝ , < ) )
39 10 19 37 38 syl3anc ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) → ( 𝐹𝑥 ) = sup ( ran 𝐹 , ℝ , < ) )
40 39 eqcomd ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) → sup ( ran 𝐹 , ℝ , < ) = ( 𝐹𝑥 ) )
41 40 19 eqeltrd ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) → sup ( ran 𝐹 , ℝ , < ) ∈ ran 𝐹 )
42 10 41 sseldd ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) → sup ( ran 𝐹 , ℝ , < ) ∈ ℝ )
43 simplrr ( ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) ∧ 𝑠𝑇 ) → ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) )
44 43 32 sylancom ( ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) ∧ 𝑠𝑇 ) → ( 𝐹𝑠 ) ≤ ( 𝐹𝑥 ) )
45 40 adantr ( ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) ∧ 𝑠𝑇 ) → sup ( ran 𝐹 , ℝ , < ) = ( 𝐹𝑥 ) )
46 44 45 breqtrrd ( ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) ∧ 𝑠𝑇 ) → ( 𝐹𝑠 ) ≤ sup ( ran 𝐹 , ℝ , < ) )
47 46 ralrimiva ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) → ∀ 𝑠𝑇 ( 𝐹𝑠 ) ≤ sup ( ran 𝐹 , ℝ , < ) )
48 30 breq1d ( 𝑡 = 𝑠 → ( ( 𝐹𝑡 ) ≤ sup ( ran 𝐹 , ℝ , < ) ↔ ( 𝐹𝑠 ) ≤ sup ( ran 𝐹 , ℝ , < ) ) )
49 48 cbvralvw ( ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ sup ( ran 𝐹 , ℝ , < ) ↔ ∀ 𝑠𝑇 ( 𝐹𝑠 ) ≤ sup ( ran 𝐹 , ℝ , < ) )
50 47 49 sylibr ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) → ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ sup ( ran 𝐹 , ℝ , < ) )
51 41 42 50 3jca ( ( 𝜑 ∧ ( 𝑥𝑇 ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ ( 𝐹𝑥 ) ) ) → ( sup ( ran 𝐹 , ℝ , < ) ∈ ran 𝐹 ∧ sup ( ran 𝐹 , ℝ , < ) ∈ ℝ ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ sup ( ran 𝐹 , ℝ , < ) ) )
52 6 51 rexlimddv ( 𝜑 → ( sup ( ran 𝐹 , ℝ , < ) ∈ ran 𝐹 ∧ sup ( ran 𝐹 , ℝ , < ) ∈ ℝ ∧ ∀ 𝑡𝑇 ( 𝐹𝑡 ) ≤ sup ( ran 𝐹 , ℝ , < ) ) )