Metamath Proof Explorer


Theorem fourierdlem70

Description: A piecewise continuous function is bounded. (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses fourierdlem70.a ( 𝜑𝐴 ∈ ℝ )
fourierdlem70.2 ( 𝜑𝐵 ∈ ℝ )
fourierdlem70.aleb ( 𝜑𝐴𝐵 )
fourierdlem70.f ( 𝜑𝐹 : ( 𝐴 [,] 𝐵 ) ⟶ ℝ )
fourierdlem70.m ( 𝜑𝑀 ∈ ℕ )
fourierdlem70.q ( 𝜑𝑄 : ( 0 ... 𝑀 ) ⟶ ℝ )
fourierdlem70.q0 ( 𝜑 → ( 𝑄 ‘ 0 ) = 𝐴 )
fourierdlem70.qm ( 𝜑 → ( 𝑄𝑀 ) = 𝐵 )
fourierdlem70.qlt ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ( 𝑄𝑖 ) < ( 𝑄 ‘ ( 𝑖 + 1 ) ) )
fourierdlem70.fcn ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ∈ ( ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) –cn→ ℂ ) )
fourierdlem70.r ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → 𝑅 ∈ ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) lim ( 𝑄𝑖 ) ) )
fourierdlem70.l ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → 𝐿 ∈ ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) lim ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) )
fourierdlem70.i 𝐼 = ( 𝑖 ∈ ( 0 ..^ 𝑀 ) ↦ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) )
Assertion fourierdlem70 ( 𝜑 → ∃ 𝑥 ∈ ℝ ∀ 𝑠 ∈ ( 𝐴 [,] 𝐵 ) ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑥 )

Proof

Step Hyp Ref Expression
1 fourierdlem70.a ( 𝜑𝐴 ∈ ℝ )
2 fourierdlem70.2 ( 𝜑𝐵 ∈ ℝ )
3 fourierdlem70.aleb ( 𝜑𝐴𝐵 )
4 fourierdlem70.f ( 𝜑𝐹 : ( 𝐴 [,] 𝐵 ) ⟶ ℝ )
5 fourierdlem70.m ( 𝜑𝑀 ∈ ℕ )
6 fourierdlem70.q ( 𝜑𝑄 : ( 0 ... 𝑀 ) ⟶ ℝ )
7 fourierdlem70.q0 ( 𝜑 → ( 𝑄 ‘ 0 ) = 𝐴 )
8 fourierdlem70.qm ( 𝜑 → ( 𝑄𝑀 ) = 𝐵 )
9 fourierdlem70.qlt ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ( 𝑄𝑖 ) < ( 𝑄 ‘ ( 𝑖 + 1 ) ) )
10 fourierdlem70.fcn ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ∈ ( ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) –cn→ ℂ ) )
11 fourierdlem70.r ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → 𝑅 ∈ ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) lim ( 𝑄𝑖 ) ) )
12 fourierdlem70.l ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → 𝐿 ∈ ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) lim ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) )
13 fourierdlem70.i 𝐼 = ( 𝑖 ∈ ( 0 ..^ 𝑀 ) ↦ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) )
14 prfi { ran 𝑄 , ran 𝐼 } ∈ Fin
15 14 a1i ( 𝜑 → { ran 𝑄 , ran 𝐼 } ∈ Fin )
16 simpr ( ( 𝜑𝑠 { ran 𝑄 , ran 𝐼 } ) → 𝑠 { ran 𝑄 , ran 𝐼 } )
17 ovex ( 0 ... 𝑀 ) ∈ V
18 fex ( ( 𝑄 : ( 0 ... 𝑀 ) ⟶ ℝ ∧ ( 0 ... 𝑀 ) ∈ V ) → 𝑄 ∈ V )
19 6 17 18 sylancl ( 𝜑𝑄 ∈ V )
20 rnexg ( 𝑄 ∈ V → ran 𝑄 ∈ V )
21 19 20 syl ( 𝜑 → ran 𝑄 ∈ V )
22 fzofi ( 0 ..^ 𝑀 ) ∈ Fin
23 13 rnmptfi ( ( 0 ..^ 𝑀 ) ∈ Fin → ran 𝐼 ∈ Fin )
24 22 23 ax-mp ran 𝐼 ∈ Fin
25 24 elexi ran 𝐼 ∈ V
26 25 uniex ran 𝐼 ∈ V
27 uniprg ( ( ran 𝑄 ∈ V ∧ ran 𝐼 ∈ V ) → { ran 𝑄 , ran 𝐼 } = ( ran 𝑄 ran 𝐼 ) )
28 21 26 27 sylancl ( 𝜑 { ran 𝑄 , ran 𝐼 } = ( ran 𝑄 ran 𝐼 ) )
29 28 adantr ( ( 𝜑𝑠 { ran 𝑄 , ran 𝐼 } ) → { ran 𝑄 , ran 𝐼 } = ( ran 𝑄 ran 𝐼 ) )
30 16 29 eleqtrd ( ( 𝜑𝑠 { ran 𝑄 , ran 𝐼 } ) → 𝑠 ∈ ( ran 𝑄 ran 𝐼 ) )
31 eqid ( 𝑦 ∈ ℕ ↦ { 𝑣 ∈ ( ℝ ↑m ( 0 ... 𝑦 ) ) ∣ ( ( ( 𝑣 ‘ 0 ) = 𝐴 ∧ ( 𝑣𝑦 ) = 𝐵 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ 𝑦 ) ( 𝑣𝑖 ) < ( 𝑣 ‘ ( 𝑖 + 1 ) ) ) } ) = ( 𝑦 ∈ ℕ ↦ { 𝑣 ∈ ( ℝ ↑m ( 0 ... 𝑦 ) ) ∣ ( ( ( 𝑣 ‘ 0 ) = 𝐴 ∧ ( 𝑣𝑦 ) = 𝐵 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ 𝑦 ) ( 𝑣𝑖 ) < ( 𝑣 ‘ ( 𝑖 + 1 ) ) ) } )
32 reex ℝ ∈ V
33 32 17 elmap ( 𝑄 ∈ ( ℝ ↑m ( 0 ... 𝑀 ) ) ↔ 𝑄 : ( 0 ... 𝑀 ) ⟶ ℝ )
34 6 33 sylibr ( 𝜑𝑄 ∈ ( ℝ ↑m ( 0 ... 𝑀 ) ) )
35 7 8 jca ( 𝜑 → ( ( 𝑄 ‘ 0 ) = 𝐴 ∧ ( 𝑄𝑀 ) = 𝐵 ) )
36 9 ralrimiva ( 𝜑 → ∀ 𝑖 ∈ ( 0 ..^ 𝑀 ) ( 𝑄𝑖 ) < ( 𝑄 ‘ ( 𝑖 + 1 ) ) )
37 34 35 36 jca32 ( 𝜑 → ( 𝑄 ∈ ( ℝ ↑m ( 0 ... 𝑀 ) ) ∧ ( ( ( 𝑄 ‘ 0 ) = 𝐴 ∧ ( 𝑄𝑀 ) = 𝐵 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ 𝑀 ) ( 𝑄𝑖 ) < ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) )
38 31 fourierdlem2 ( 𝑀 ∈ ℕ → ( 𝑄 ∈ ( ( 𝑦 ∈ ℕ ↦ { 𝑣 ∈ ( ℝ ↑m ( 0 ... 𝑦 ) ) ∣ ( ( ( 𝑣 ‘ 0 ) = 𝐴 ∧ ( 𝑣𝑦 ) = 𝐵 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ 𝑦 ) ( 𝑣𝑖 ) < ( 𝑣 ‘ ( 𝑖 + 1 ) ) ) } ) ‘ 𝑀 ) ↔ ( 𝑄 ∈ ( ℝ ↑m ( 0 ... 𝑀 ) ) ∧ ( ( ( 𝑄 ‘ 0 ) = 𝐴 ∧ ( 𝑄𝑀 ) = 𝐵 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ 𝑀 ) ( 𝑄𝑖 ) < ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ) )
39 5 38 syl ( 𝜑 → ( 𝑄 ∈ ( ( 𝑦 ∈ ℕ ↦ { 𝑣 ∈ ( ℝ ↑m ( 0 ... 𝑦 ) ) ∣ ( ( ( 𝑣 ‘ 0 ) = 𝐴 ∧ ( 𝑣𝑦 ) = 𝐵 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ 𝑦 ) ( 𝑣𝑖 ) < ( 𝑣 ‘ ( 𝑖 + 1 ) ) ) } ) ‘ 𝑀 ) ↔ ( 𝑄 ∈ ( ℝ ↑m ( 0 ... 𝑀 ) ) ∧ ( ( ( 𝑄 ‘ 0 ) = 𝐴 ∧ ( 𝑄𝑀 ) = 𝐵 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ 𝑀 ) ( 𝑄𝑖 ) < ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ) )
40 37 39 mpbird ( 𝜑𝑄 ∈ ( ( 𝑦 ∈ ℕ ↦ { 𝑣 ∈ ( ℝ ↑m ( 0 ... 𝑦 ) ) ∣ ( ( ( 𝑣 ‘ 0 ) = 𝐴 ∧ ( 𝑣𝑦 ) = 𝐵 ) ∧ ∀ 𝑖 ∈ ( 0 ..^ 𝑦 ) ( 𝑣𝑖 ) < ( 𝑣 ‘ ( 𝑖 + 1 ) ) ) } ) ‘ 𝑀 ) )
41 31 5 40 fourierdlem15 ( 𝜑𝑄 : ( 0 ... 𝑀 ) ⟶ ( 𝐴 [,] 𝐵 ) )
42 41 frnd ( 𝜑 → ran 𝑄 ⊆ ( 𝐴 [,] 𝐵 ) )
43 42 sselda ( ( 𝜑𝑠 ∈ ran 𝑄 ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) )
44 43 adantlr ( ( ( 𝜑𝑠 ∈ ( ran 𝑄 ran 𝐼 ) ) ∧ 𝑠 ∈ ran 𝑄 ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) )
45 simpll ( ( ( 𝜑𝑠 ∈ ( ran 𝑄 ran 𝐼 ) ) ∧ ¬ 𝑠 ∈ ran 𝑄 ) → 𝜑 )
46 elunnel1 ( ( 𝑠 ∈ ( ran 𝑄 ran 𝐼 ) ∧ ¬ 𝑠 ∈ ran 𝑄 ) → 𝑠 ran 𝐼 )
47 46 adantll ( ( ( 𝜑𝑠 ∈ ( ran 𝑄 ran 𝐼 ) ) ∧ ¬ 𝑠 ∈ ran 𝑄 ) → 𝑠 ran 𝐼 )
48 simpr ( ( 𝜑𝑠 ran 𝐼 ) → 𝑠 ran 𝐼 )
49 13 funmpt2 Fun 𝐼
50 elunirn ( Fun 𝐼 → ( 𝑠 ran 𝐼 ↔ ∃ 𝑖 ∈ dom 𝐼 𝑠 ∈ ( 𝐼𝑖 ) ) )
51 49 50 mp1i ( ( 𝜑𝑠 ran 𝐼 ) → ( 𝑠 ran 𝐼 ↔ ∃ 𝑖 ∈ dom 𝐼 𝑠 ∈ ( 𝐼𝑖 ) ) )
52 48 51 mpbid ( ( 𝜑𝑠 ran 𝐼 ) → ∃ 𝑖 ∈ dom 𝐼 𝑠 ∈ ( 𝐼𝑖 ) )
53 id ( 𝑖 ∈ dom 𝐼𝑖 ∈ dom 𝐼 )
54 ovex ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ∈ V
55 54 13 dmmpti dom 𝐼 = ( 0 ..^ 𝑀 )
56 53 55 eleqtrdi ( 𝑖 ∈ dom 𝐼𝑖 ∈ ( 0 ..^ 𝑀 ) )
57 13 fvmpt2 ( ( 𝑖 ∈ ( 0 ..^ 𝑀 ) ∧ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ∈ V ) → ( 𝐼𝑖 ) = ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) )
58 56 54 57 sylancl ( 𝑖 ∈ dom 𝐼 → ( 𝐼𝑖 ) = ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) )
59 58 adantl ( ( 𝜑𝑖 ∈ dom 𝐼 ) → ( 𝐼𝑖 ) = ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) )
60 ioossicc ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ⊆ ( ( 𝑄𝑖 ) [,] ( 𝑄 ‘ ( 𝑖 + 1 ) ) )
61 1 rexrd ( 𝜑𝐴 ∈ ℝ* )
62 61 adantr ( ( 𝜑𝑖 ∈ dom 𝐼 ) → 𝐴 ∈ ℝ* )
63 2 rexrd ( 𝜑𝐵 ∈ ℝ* )
64 63 adantr ( ( 𝜑𝑖 ∈ dom 𝐼 ) → 𝐵 ∈ ℝ* )
65 41 adantr ( ( 𝜑𝑖 ∈ dom 𝐼 ) → 𝑄 : ( 0 ... 𝑀 ) ⟶ ( 𝐴 [,] 𝐵 ) )
66 56 adantl ( ( 𝜑𝑖 ∈ dom 𝐼 ) → 𝑖 ∈ ( 0 ..^ 𝑀 ) )
67 62 64 65 66 fourierdlem8 ( ( 𝜑𝑖 ∈ dom 𝐼 ) → ( ( 𝑄𝑖 ) [,] ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ⊆ ( 𝐴 [,] 𝐵 ) )
68 60 67 sstrid ( ( 𝜑𝑖 ∈ dom 𝐼 ) → ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ⊆ ( 𝐴 [,] 𝐵 ) )
69 59 68 eqsstrd ( ( 𝜑𝑖 ∈ dom 𝐼 ) → ( 𝐼𝑖 ) ⊆ ( 𝐴 [,] 𝐵 ) )
70 69 3adant3 ( ( 𝜑𝑖 ∈ dom 𝐼𝑠 ∈ ( 𝐼𝑖 ) ) → ( 𝐼𝑖 ) ⊆ ( 𝐴 [,] 𝐵 ) )
71 simp3 ( ( 𝜑𝑖 ∈ dom 𝐼𝑠 ∈ ( 𝐼𝑖 ) ) → 𝑠 ∈ ( 𝐼𝑖 ) )
72 70 71 sseldd ( ( 𝜑𝑖 ∈ dom 𝐼𝑠 ∈ ( 𝐼𝑖 ) ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) )
73 72 3exp ( 𝜑 → ( 𝑖 ∈ dom 𝐼 → ( 𝑠 ∈ ( 𝐼𝑖 ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) ) ) )
74 73 adantr ( ( 𝜑𝑠 ran 𝐼 ) → ( 𝑖 ∈ dom 𝐼 → ( 𝑠 ∈ ( 𝐼𝑖 ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) ) ) )
75 74 rexlimdv ( ( 𝜑𝑠 ran 𝐼 ) → ( ∃ 𝑖 ∈ dom 𝐼 𝑠 ∈ ( 𝐼𝑖 ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) ) )
76 52 75 mpd ( ( 𝜑𝑠 ran 𝐼 ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) )
77 45 47 76 syl2anc ( ( ( 𝜑𝑠 ∈ ( ran 𝑄 ran 𝐼 ) ) ∧ ¬ 𝑠 ∈ ran 𝑄 ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) )
78 44 77 pm2.61dan ( ( 𝜑𝑠 ∈ ( ran 𝑄 ran 𝐼 ) ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) )
79 30 78 syldan ( ( 𝜑𝑠 { ran 𝑄 , ran 𝐼 } ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) )
80 4 ffvelrnda ( ( 𝜑𝑠 ∈ ( 𝐴 [,] 𝐵 ) ) → ( 𝐹𝑠 ) ∈ ℝ )
81 79 80 syldan ( ( 𝜑𝑠 { ran 𝑄 , ran 𝐼 } ) → ( 𝐹𝑠 ) ∈ ℝ )
82 81 recnd ( ( 𝜑𝑠 { ran 𝑄 , ran 𝐼 } ) → ( 𝐹𝑠 ) ∈ ℂ )
83 82 abscld ( ( 𝜑𝑠 { ran 𝑄 , ran 𝐼 } ) → ( abs ‘ ( 𝐹𝑠 ) ) ∈ ℝ )
84 simpr ( ( 𝜑𝑤 = ran 𝑄 ) → 𝑤 = ran 𝑄 )
85 6 adantr ( ( 𝜑𝑤 = ran 𝑄 ) → 𝑄 : ( 0 ... 𝑀 ) ⟶ ℝ )
86 fzfid ( ( 𝜑𝑤 = ran 𝑄 ) → ( 0 ... 𝑀 ) ∈ Fin )
87 rnffi ( ( 𝑄 : ( 0 ... 𝑀 ) ⟶ ℝ ∧ ( 0 ... 𝑀 ) ∈ Fin ) → ran 𝑄 ∈ Fin )
88 85 86 87 syl2anc ( ( 𝜑𝑤 = ran 𝑄 ) → ran 𝑄 ∈ Fin )
89 84 88 eqeltrd ( ( 𝜑𝑤 = ran 𝑄 ) → 𝑤 ∈ Fin )
90 89 adantlr ( ( ( 𝜑𝑤 ∈ { ran 𝑄 , ran 𝐼 } ) ∧ 𝑤 = ran 𝑄 ) → 𝑤 ∈ Fin )
91 4 ad2antrr ( ( ( 𝜑𝑤 = ran 𝑄 ) ∧ 𝑠𝑤 ) → 𝐹 : ( 𝐴 [,] 𝐵 ) ⟶ ℝ )
92 simpll ( ( ( 𝜑𝑤 = ran 𝑄 ) ∧ 𝑠𝑤 ) → 𝜑 )
93 simpr ( ( 𝑤 = ran 𝑄𝑠𝑤 ) → 𝑠𝑤 )
94 simpl ( ( 𝑤 = ran 𝑄𝑠𝑤 ) → 𝑤 = ran 𝑄 )
95 93 94 eleqtrd ( ( 𝑤 = ran 𝑄𝑠𝑤 ) → 𝑠 ∈ ran 𝑄 )
96 95 adantll ( ( ( 𝜑𝑤 = ran 𝑄 ) ∧ 𝑠𝑤 ) → 𝑠 ∈ ran 𝑄 )
97 92 96 43 syl2anc ( ( ( 𝜑𝑤 = ran 𝑄 ) ∧ 𝑠𝑤 ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) )
98 91 97 ffvelrnd ( ( ( 𝜑𝑤 = ran 𝑄 ) ∧ 𝑠𝑤 ) → ( 𝐹𝑠 ) ∈ ℝ )
99 98 recnd ( ( ( 𝜑𝑤 = ran 𝑄 ) ∧ 𝑠𝑤 ) → ( 𝐹𝑠 ) ∈ ℂ )
100 99 abscld ( ( ( 𝜑𝑤 = ran 𝑄 ) ∧ 𝑠𝑤 ) → ( abs ‘ ( 𝐹𝑠 ) ) ∈ ℝ )
101 100 ralrimiva ( ( 𝜑𝑤 = ran 𝑄 ) → ∀ 𝑠𝑤 ( abs ‘ ( 𝐹𝑠 ) ) ∈ ℝ )
102 101 adantlr ( ( ( 𝜑𝑤 ∈ { ran 𝑄 , ran 𝐼 } ) ∧ 𝑤 = ran 𝑄 ) → ∀ 𝑠𝑤 ( abs ‘ ( 𝐹𝑠 ) ) ∈ ℝ )
103 fimaxre3 ( ( 𝑤 ∈ Fin ∧ ∀ 𝑠𝑤 ( abs ‘ ( 𝐹𝑠 ) ) ∈ ℝ ) → ∃ 𝑧 ∈ ℝ ∀ 𝑠𝑤 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑧 )
104 90 102 103 syl2anc ( ( ( 𝜑𝑤 ∈ { ran 𝑄 , ran 𝐼 } ) ∧ 𝑤 = ran 𝑄 ) → ∃ 𝑧 ∈ ℝ ∀ 𝑠𝑤 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑧 )
105 simpll ( ( ( 𝜑𝑤 ∈ { ran 𝑄 , ran 𝐼 } ) ∧ ¬ 𝑤 = ran 𝑄 ) → 𝜑 )
106 neqne ( ¬ 𝑤 = ran 𝑄𝑤 ≠ ran 𝑄 )
107 elprn1 ( ( 𝑤 ∈ { ran 𝑄 , ran 𝐼 } ∧ 𝑤 ≠ ran 𝑄 ) → 𝑤 = ran 𝐼 )
108 106 107 sylan2 ( ( 𝑤 ∈ { ran 𝑄 , ran 𝐼 } ∧ ¬ 𝑤 = ran 𝑄 ) → 𝑤 = ran 𝐼 )
109 108 adantll ( ( ( 𝜑𝑤 ∈ { ran 𝑄 , ran 𝐼 } ) ∧ ¬ 𝑤 = ran 𝑄 ) → 𝑤 = ran 𝐼 )
110 22 23 mp1i ( ( 𝜑𝑤 = ran 𝐼 ) → ran 𝐼 ∈ Fin )
111 ax-resscn ℝ ⊆ ℂ
112 111 a1i ( 𝜑 → ℝ ⊆ ℂ )
113 4 112 fssd ( 𝜑𝐹 : ( 𝐴 [,] 𝐵 ) ⟶ ℂ )
114 113 ad2antrr ( ( ( 𝜑𝑤 = ran 𝐼 ) ∧ 𝑠 ran 𝐼 ) → 𝐹 : ( 𝐴 [,] 𝐵 ) ⟶ ℂ )
115 76 adantlr ( ( ( 𝜑𝑤 = ran 𝐼 ) ∧ 𝑠 ran 𝐼 ) → 𝑠 ∈ ( 𝐴 [,] 𝐵 ) )
116 114 115 ffvelrnd ( ( ( 𝜑𝑤 = ran 𝐼 ) ∧ 𝑠 ran 𝐼 ) → ( 𝐹𝑠 ) ∈ ℂ )
117 116 abscld ( ( ( 𝜑𝑤 = ran 𝐼 ) ∧ 𝑠 ran 𝐼 ) → ( abs ‘ ( 𝐹𝑠 ) ) ∈ ℝ )
118 54 13 fnmpti 𝐼 Fn ( 0 ..^ 𝑀 )
119 fvelrnb ( 𝐼 Fn ( 0 ..^ 𝑀 ) → ( 𝑡 ∈ ran 𝐼 ↔ ∃ 𝑖 ∈ ( 0 ..^ 𝑀 ) ( 𝐼𝑖 ) = 𝑡 ) )
120 118 119 ax-mp ( 𝑡 ∈ ran 𝐼 ↔ ∃ 𝑖 ∈ ( 0 ..^ 𝑀 ) ( 𝐼𝑖 ) = 𝑡 )
121 120 biimpi ( 𝑡 ∈ ran 𝐼 → ∃ 𝑖 ∈ ( 0 ..^ 𝑀 ) ( 𝐼𝑖 ) = 𝑡 )
122 121 adantl ( ( 𝜑𝑡 ∈ ran 𝐼 ) → ∃ 𝑖 ∈ ( 0 ..^ 𝑀 ) ( 𝐼𝑖 ) = 𝑡 )
123 6 adantr ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → 𝑄 : ( 0 ... 𝑀 ) ⟶ ℝ )
124 elfzofz ( 𝑖 ∈ ( 0 ..^ 𝑀 ) → 𝑖 ∈ ( 0 ... 𝑀 ) )
125 124 adantl ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → 𝑖 ∈ ( 0 ... 𝑀 ) )
126 123 125 ffvelrnd ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ( 𝑄𝑖 ) ∈ ℝ )
127 fzofzp1 ( 𝑖 ∈ ( 0 ..^ 𝑀 ) → ( 𝑖 + 1 ) ∈ ( 0 ... 𝑀 ) )
128 127 adantl ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ( 𝑖 + 1 ) ∈ ( 0 ... 𝑀 ) )
129 123 128 ffvelrnd ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ( 𝑄 ‘ ( 𝑖 + 1 ) ) ∈ ℝ )
130 126 129 10 12 11 cncfioobd ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ∃ 𝑏 ∈ ℝ ∀ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ( abs ‘ ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ‘ 𝑠 ) ) ≤ 𝑏 )
131 fvres ( 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) → ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ‘ 𝑠 ) = ( 𝐹𝑠 ) )
132 131 fveq2d ( 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) → ( abs ‘ ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ‘ 𝑠 ) ) = ( abs ‘ ( 𝐹𝑠 ) ) )
133 132 breq1d ( 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) → ( ( abs ‘ ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ‘ 𝑠 ) ) ≤ 𝑏 ↔ ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ) )
134 133 adantl ( ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) ∧ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) → ( ( abs ‘ ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ‘ 𝑠 ) ) ≤ 𝑏 ↔ ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ) )
135 134 ralbidva ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ( ∀ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ( abs ‘ ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ‘ 𝑠 ) ) ≤ 𝑏 ↔ ∀ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ) )
136 135 rexbidv ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ( ∃ 𝑏 ∈ ℝ ∀ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ( abs ‘ ( ( 𝐹 ↾ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) ‘ 𝑠 ) ) ≤ 𝑏 ↔ ∃ 𝑏 ∈ ℝ ∀ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ) )
137 130 136 mpbid ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ) → ∃ 𝑏 ∈ ℝ ∀ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 )
138 137 3adant3 ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ∧ ( 𝐼𝑖 ) = 𝑡 ) → ∃ 𝑏 ∈ ℝ ∀ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 )
139 54 57 mpan2 ( 𝑖 ∈ ( 0 ..^ 𝑀 ) → ( 𝐼𝑖 ) = ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) )
140 139 eqcomd ( 𝑖 ∈ ( 0 ..^ 𝑀 ) → ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) = ( 𝐼𝑖 ) )
141 140 adantr ( ( 𝑖 ∈ ( 0 ..^ 𝑀 ) ∧ ( 𝐼𝑖 ) = 𝑡 ) → ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) = ( 𝐼𝑖 ) )
142 simpr ( ( 𝑖 ∈ ( 0 ..^ 𝑀 ) ∧ ( 𝐼𝑖 ) = 𝑡 ) → ( 𝐼𝑖 ) = 𝑡 )
143 141 142 eqtrd ( ( 𝑖 ∈ ( 0 ..^ 𝑀 ) ∧ ( 𝐼𝑖 ) = 𝑡 ) → ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) = 𝑡 )
144 143 raleqdv ( ( 𝑖 ∈ ( 0 ..^ 𝑀 ) ∧ ( 𝐼𝑖 ) = 𝑡 ) → ( ∀ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ↔ ∀ 𝑠𝑡 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ) )
145 144 rexbidv ( ( 𝑖 ∈ ( 0 ..^ 𝑀 ) ∧ ( 𝐼𝑖 ) = 𝑡 ) → ( ∃ 𝑏 ∈ ℝ ∀ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ↔ ∃ 𝑏 ∈ ℝ ∀ 𝑠𝑡 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ) )
146 145 3adant1 ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ∧ ( 𝐼𝑖 ) = 𝑡 ) → ( ∃ 𝑏 ∈ ℝ ∀ 𝑠 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ↔ ∃ 𝑏 ∈ ℝ ∀ 𝑠𝑡 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ) )
147 138 146 mpbid ( ( 𝜑𝑖 ∈ ( 0 ..^ 𝑀 ) ∧ ( 𝐼𝑖 ) = 𝑡 ) → ∃ 𝑏 ∈ ℝ ∀ 𝑠𝑡 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 )
148 147 3exp ( 𝜑 → ( 𝑖 ∈ ( 0 ..^ 𝑀 ) → ( ( 𝐼𝑖 ) = 𝑡 → ∃ 𝑏 ∈ ℝ ∀ 𝑠𝑡 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ) ) )
149 148 adantr ( ( 𝜑𝑡 ∈ ran 𝐼 ) → ( 𝑖 ∈ ( 0 ..^ 𝑀 ) → ( ( 𝐼𝑖 ) = 𝑡 → ∃ 𝑏 ∈ ℝ ∀ 𝑠𝑡 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ) ) )
150 149 rexlimdv ( ( 𝜑𝑡 ∈ ran 𝐼 ) → ( ∃ 𝑖 ∈ ( 0 ..^ 𝑀 ) ( 𝐼𝑖 ) = 𝑡 → ∃ 𝑏 ∈ ℝ ∀ 𝑠𝑡 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 ) )
151 122 150 mpd ( ( 𝜑𝑡 ∈ ran 𝐼 ) → ∃ 𝑏 ∈ ℝ ∀ 𝑠𝑡 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 )
152 151 adantlr ( ( ( 𝜑𝑤 = ran 𝐼 ) ∧ 𝑡 ∈ ran 𝐼 ) → ∃ 𝑏 ∈ ℝ ∀ 𝑠𝑡 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑏 )
153 eqimss ( 𝑤 = ran 𝐼𝑤 ran 𝐼 )
154 153 adantl ( ( 𝜑𝑤 = ran 𝐼 ) → 𝑤 ran 𝐼 )
155 110 117 152 154 ssfiunibd ( ( 𝜑𝑤 = ran 𝐼 ) → ∃ 𝑧 ∈ ℝ ∀ 𝑠𝑤 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑧 )
156 105 109 155 syl2anc ( ( ( 𝜑𝑤 ∈ { ran 𝑄 , ran 𝐼 } ) ∧ ¬ 𝑤 = ran 𝑄 ) → ∃ 𝑧 ∈ ℝ ∀ 𝑠𝑤 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑧 )
157 104 156 pm2.61dan ( ( 𝜑𝑤 ∈ { ran 𝑄 , ran 𝐼 } ) → ∃ 𝑧 ∈ ℝ ∀ 𝑠𝑤 ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑧 )
158 5 ad2antrr ( ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) ∧ ¬ 𝑡 ∈ ran 𝑄 ) → 𝑀 ∈ ℕ )
159 6 ad2antrr ( ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) ∧ ¬ 𝑡 ∈ ran 𝑄 ) → 𝑄 : ( 0 ... 𝑀 ) ⟶ ℝ )
160 simpr ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) → 𝑡 ∈ ( 𝐴 [,] 𝐵 ) )
161 7 eqcomd ( 𝜑𝐴 = ( 𝑄 ‘ 0 ) )
162 8 eqcomd ( 𝜑𝐵 = ( 𝑄𝑀 ) )
163 161 162 oveq12d ( 𝜑 → ( 𝐴 [,] 𝐵 ) = ( ( 𝑄 ‘ 0 ) [,] ( 𝑄𝑀 ) ) )
164 163 adantr ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) → ( 𝐴 [,] 𝐵 ) = ( ( 𝑄 ‘ 0 ) [,] ( 𝑄𝑀 ) ) )
165 160 164 eleqtrd ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) → 𝑡 ∈ ( ( 𝑄 ‘ 0 ) [,] ( 𝑄𝑀 ) ) )
166 165 adantr ( ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) ∧ ¬ 𝑡 ∈ ran 𝑄 ) → 𝑡 ∈ ( ( 𝑄 ‘ 0 ) [,] ( 𝑄𝑀 ) ) )
167 simpr ( ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) ∧ ¬ 𝑡 ∈ ran 𝑄 ) → ¬ 𝑡 ∈ ran 𝑄 )
168 fveq2 ( 𝑘 = 𝑗 → ( 𝑄𝑘 ) = ( 𝑄𝑗 ) )
169 168 breq1d ( 𝑘 = 𝑗 → ( ( 𝑄𝑘 ) < 𝑡 ↔ ( 𝑄𝑗 ) < 𝑡 ) )
170 169 cbvrabv { 𝑘 ∈ ( 0 ..^ 𝑀 ) ∣ ( 𝑄𝑘 ) < 𝑡 } = { 𝑗 ∈ ( 0 ..^ 𝑀 ) ∣ ( 𝑄𝑗 ) < 𝑡 }
171 170 supeq1i sup ( { 𝑘 ∈ ( 0 ..^ 𝑀 ) ∣ ( 𝑄𝑘 ) < 𝑡 } , ℝ , < ) = sup ( { 𝑗 ∈ ( 0 ..^ 𝑀 ) ∣ ( 𝑄𝑗 ) < 𝑡 } , ℝ , < )
172 158 159 166 167 171 fourierdlem25 ( ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) ∧ ¬ 𝑡 ∈ ran 𝑄 ) → ∃ 𝑖 ∈ ( 0 ..^ 𝑀 ) 𝑡 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) )
173 139 eleq2d ( 𝑖 ∈ ( 0 ..^ 𝑀 ) → ( 𝑡 ∈ ( 𝐼𝑖 ) ↔ 𝑡 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) ) )
174 173 rexbiia ( ∃ 𝑖 ∈ ( 0 ..^ 𝑀 ) 𝑡 ∈ ( 𝐼𝑖 ) ↔ ∃ 𝑖 ∈ ( 0 ..^ 𝑀 ) 𝑡 ∈ ( ( 𝑄𝑖 ) (,) ( 𝑄 ‘ ( 𝑖 + 1 ) ) ) )
175 172 174 sylibr ( ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) ∧ ¬ 𝑡 ∈ ran 𝑄 ) → ∃ 𝑖 ∈ ( 0 ..^ 𝑀 ) 𝑡 ∈ ( 𝐼𝑖 ) )
176 55 eqcomi ( 0 ..^ 𝑀 ) = dom 𝐼
177 176 rexeqi ( ∃ 𝑖 ∈ ( 0 ..^ 𝑀 ) 𝑡 ∈ ( 𝐼𝑖 ) ↔ ∃ 𝑖 ∈ dom 𝐼 𝑡 ∈ ( 𝐼𝑖 ) )
178 175 177 sylib ( ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) ∧ ¬ 𝑡 ∈ ran 𝑄 ) → ∃ 𝑖 ∈ dom 𝐼 𝑡 ∈ ( 𝐼𝑖 ) )
179 elunirn ( Fun 𝐼 → ( 𝑡 ran 𝐼 ↔ ∃ 𝑖 ∈ dom 𝐼 𝑡 ∈ ( 𝐼𝑖 ) ) )
180 49 179 mp1i ( ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) ∧ ¬ 𝑡 ∈ ran 𝑄 ) → ( 𝑡 ran 𝐼 ↔ ∃ 𝑖 ∈ dom 𝐼 𝑡 ∈ ( 𝐼𝑖 ) ) )
181 178 180 mpbird ( ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) ∧ ¬ 𝑡 ∈ ran 𝑄 ) → 𝑡 ran 𝐼 )
182 181 ex ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) → ( ¬ 𝑡 ∈ ran 𝑄𝑡 ran 𝐼 ) )
183 182 orrd ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) → ( 𝑡 ∈ ran 𝑄𝑡 ran 𝐼 ) )
184 elun ( 𝑡 ∈ ( ran 𝑄 ran 𝐼 ) ↔ ( 𝑡 ∈ ran 𝑄𝑡 ran 𝐼 ) )
185 183 184 sylibr ( ( 𝜑𝑡 ∈ ( 𝐴 [,] 𝐵 ) ) → 𝑡 ∈ ( ran 𝑄 ran 𝐼 ) )
186 185 ralrimiva ( 𝜑 → ∀ 𝑡 ∈ ( 𝐴 [,] 𝐵 ) 𝑡 ∈ ( ran 𝑄 ran 𝐼 ) )
187 dfss3 ( ( 𝐴 [,] 𝐵 ) ⊆ ( ran 𝑄 ran 𝐼 ) ↔ ∀ 𝑡 ∈ ( 𝐴 [,] 𝐵 ) 𝑡 ∈ ( ran 𝑄 ran 𝐼 ) )
188 186 187 sylibr ( 𝜑 → ( 𝐴 [,] 𝐵 ) ⊆ ( ran 𝑄 ran 𝐼 ) )
189 188 28 sseqtrrd ( 𝜑 → ( 𝐴 [,] 𝐵 ) ⊆ { ran 𝑄 , ran 𝐼 } )
190 15 83 157 189 ssfiunibd ( 𝜑 → ∃ 𝑥 ∈ ℝ ∀ 𝑠 ∈ ( 𝐴 [,] 𝐵 ) ( abs ‘ ( 𝐹𝑠 ) ) ≤ 𝑥 )