Metamath Proof Explorer


Theorem stoweidlem37

Description: This lemma is used to prove the existence of a function p as in Lemma 1 of BrosowskiDeutsh p. 90: p is in the subalgebra, such that 0 <= p <= 1, p__(t_0) = 0, and p > 0 on T - U. Z is used for t_0, P is used for p, ( Gi ) is used for p__(t_i). (Contributed by Glauco Siliprandi, 20-Apr-2017)

Ref Expression
Hypotheses stoweidlem37.1 𝑄 = { 𝐴 ∣ ( ( 𝑍 ) = 0 ∧ ∀ 𝑡𝑇 ( 0 ≤ ( 𝑡 ) ∧ ( 𝑡 ) ≤ 1 ) ) }
stoweidlem37.2 𝑃 = ( 𝑡𝑇 ↦ ( ( 1 / 𝑀 ) · Σ 𝑖 ∈ ( 1 ... 𝑀 ) ( ( 𝐺𝑖 ) ‘ 𝑡 ) ) )
stoweidlem37.3 ( 𝜑𝑀 ∈ ℕ )
stoweidlem37.4 ( 𝜑𝐺 : ( 1 ... 𝑀 ) ⟶ 𝑄 )
stoweidlem37.5 ( ( 𝜑𝑓𝐴 ) → 𝑓 : 𝑇 ⟶ ℝ )
stoweidlem37.6 ( 𝜑𝑍𝑇 )
Assertion stoweidlem37 ( 𝜑 → ( 𝑃𝑍 ) = 0 )

Proof

Step Hyp Ref Expression
1 stoweidlem37.1 𝑄 = { 𝐴 ∣ ( ( 𝑍 ) = 0 ∧ ∀ 𝑡𝑇 ( 0 ≤ ( 𝑡 ) ∧ ( 𝑡 ) ≤ 1 ) ) }
2 stoweidlem37.2 𝑃 = ( 𝑡𝑇 ↦ ( ( 1 / 𝑀 ) · Σ 𝑖 ∈ ( 1 ... 𝑀 ) ( ( 𝐺𝑖 ) ‘ 𝑡 ) ) )
3 stoweidlem37.3 ( 𝜑𝑀 ∈ ℕ )
4 stoweidlem37.4 ( 𝜑𝐺 : ( 1 ... 𝑀 ) ⟶ 𝑄 )
5 stoweidlem37.5 ( ( 𝜑𝑓𝐴 ) → 𝑓 : 𝑇 ⟶ ℝ )
6 stoweidlem37.6 ( 𝜑𝑍𝑇 )
7 1 2 3 4 5 stoweidlem30 ( ( 𝜑𝑍𝑇 ) → ( 𝑃𝑍 ) = ( ( 1 / 𝑀 ) · Σ 𝑖 ∈ ( 1 ... 𝑀 ) ( ( 𝐺𝑖 ) ‘ 𝑍 ) ) )
8 6 7 mpdan ( 𝜑 → ( 𝑃𝑍 ) = ( ( 1 / 𝑀 ) · Σ 𝑖 ∈ ( 1 ... 𝑀 ) ( ( 𝐺𝑖 ) ‘ 𝑍 ) ) )
9 4 ffvelrnda ( ( 𝜑𝑖 ∈ ( 1 ... 𝑀 ) ) → ( 𝐺𝑖 ) ∈ 𝑄 )
10 fveq1 ( = ( 𝐺𝑖 ) → ( 𝑍 ) = ( ( 𝐺𝑖 ) ‘ 𝑍 ) )
11 10 eqeq1d ( = ( 𝐺𝑖 ) → ( ( 𝑍 ) = 0 ↔ ( ( 𝐺𝑖 ) ‘ 𝑍 ) = 0 ) )
12 fveq1 ( = ( 𝐺𝑖 ) → ( 𝑡 ) = ( ( 𝐺𝑖 ) ‘ 𝑡 ) )
13 12 breq2d ( = ( 𝐺𝑖 ) → ( 0 ≤ ( 𝑡 ) ↔ 0 ≤ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ) )
14 12 breq1d ( = ( 𝐺𝑖 ) → ( ( 𝑡 ) ≤ 1 ↔ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ≤ 1 ) )
15 13 14 anbi12d ( = ( 𝐺𝑖 ) → ( ( 0 ≤ ( 𝑡 ) ∧ ( 𝑡 ) ≤ 1 ) ↔ ( 0 ≤ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ∧ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ≤ 1 ) ) )
16 15 ralbidv ( = ( 𝐺𝑖 ) → ( ∀ 𝑡𝑇 ( 0 ≤ ( 𝑡 ) ∧ ( 𝑡 ) ≤ 1 ) ↔ ∀ 𝑡𝑇 ( 0 ≤ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ∧ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ≤ 1 ) ) )
17 11 16 anbi12d ( = ( 𝐺𝑖 ) → ( ( ( 𝑍 ) = 0 ∧ ∀ 𝑡𝑇 ( 0 ≤ ( 𝑡 ) ∧ ( 𝑡 ) ≤ 1 ) ) ↔ ( ( ( 𝐺𝑖 ) ‘ 𝑍 ) = 0 ∧ ∀ 𝑡𝑇 ( 0 ≤ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ∧ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ≤ 1 ) ) ) )
18 17 1 elrab2 ( ( 𝐺𝑖 ) ∈ 𝑄 ↔ ( ( 𝐺𝑖 ) ∈ 𝐴 ∧ ( ( ( 𝐺𝑖 ) ‘ 𝑍 ) = 0 ∧ ∀ 𝑡𝑇 ( 0 ≤ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ∧ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ≤ 1 ) ) ) )
19 9 18 sylib ( ( 𝜑𝑖 ∈ ( 1 ... 𝑀 ) ) → ( ( 𝐺𝑖 ) ∈ 𝐴 ∧ ( ( ( 𝐺𝑖 ) ‘ 𝑍 ) = 0 ∧ ∀ 𝑡𝑇 ( 0 ≤ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ∧ ( ( 𝐺𝑖 ) ‘ 𝑡 ) ≤ 1 ) ) ) )
20 19 simprld ( ( 𝜑𝑖 ∈ ( 1 ... 𝑀 ) ) → ( ( 𝐺𝑖 ) ‘ 𝑍 ) = 0 )
21 20 sumeq2dv ( 𝜑 → Σ 𝑖 ∈ ( 1 ... 𝑀 ) ( ( 𝐺𝑖 ) ‘ 𝑍 ) = Σ 𝑖 ∈ ( 1 ... 𝑀 ) 0 )
22 fzfi ( 1 ... 𝑀 ) ∈ Fin
23 olc ( ( 1 ... 𝑀 ) ∈ Fin → ( ( 1 ... 𝑀 ) ⊆ ( ℤ ‘ 1 ) ∨ ( 1 ... 𝑀 ) ∈ Fin ) )
24 sumz ( ( ( 1 ... 𝑀 ) ⊆ ( ℤ ‘ 1 ) ∨ ( 1 ... 𝑀 ) ∈ Fin ) → Σ 𝑖 ∈ ( 1 ... 𝑀 ) 0 = 0 )
25 22 23 24 mp2b Σ 𝑖 ∈ ( 1 ... 𝑀 ) 0 = 0
26 21 25 eqtrdi ( 𝜑 → Σ 𝑖 ∈ ( 1 ... 𝑀 ) ( ( 𝐺𝑖 ) ‘ 𝑍 ) = 0 )
27 26 oveq2d ( 𝜑 → ( ( 1 / 𝑀 ) · Σ 𝑖 ∈ ( 1 ... 𝑀 ) ( ( 𝐺𝑖 ) ‘ 𝑍 ) ) = ( ( 1 / 𝑀 ) · 0 ) )
28 3 nncnd ( 𝜑𝑀 ∈ ℂ )
29 3 nnne0d ( 𝜑𝑀 ≠ 0 )
30 28 29 reccld ( 𝜑 → ( 1 / 𝑀 ) ∈ ℂ )
31 30 mul01d ( 𝜑 → ( ( 1 / 𝑀 ) · 0 ) = 0 )
32 8 27 31 3eqtrd ( 𝜑 → ( 𝑃𝑍 ) = 0 )