Intuitionistic Logic Explorer < Previous   Next > Nearby theorems Mirrors  >  Home  >  ILE Home  >  Th. List  >  supinfneg GIF version

Theorem supinfneg 8816
 Description: If a set of real numbers has a least upper bound, the set of the negation of those numbers has a greatest lower bound. For a theorem which is similar but only for the boundedness part, see ublbneg 8831. (Contributed by Jim Kingdon, 15-Jan-2022.)
Hypotheses
Ref Expression
supinfneg.ex (𝜑 → ∃𝑥 ∈ ℝ (∀𝑦𝐴 ¬ 𝑥 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧𝐴 𝑦 < 𝑧)))
supinfneg.ss (𝜑𝐴 ⊆ ℝ)
Assertion
Ref Expression
supinfneg (𝜑 → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦)))
Distinct variable groups:   𝑦,𝐴,𝑧,𝑤,𝑥   𝜑,𝑦
Allowed substitution hints:   𝜑(𝑥,𝑧,𝑤)

Proof of Theorem supinfneg
Dummy variables 𝑎 𝑏 𝑐 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 supinfneg.ex . . . 4 (𝜑 → ∃𝑥 ∈ ℝ (∀𝑦𝐴 ¬ 𝑥 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧𝐴 𝑦 < 𝑧)))
2 breq1 3808 . . . . . . . 8 (𝑎 = 𝑥 → (𝑎 < 𝑦𝑥 < 𝑦))
32notbid 625 . . . . . . 7 (𝑎 = 𝑥 → (¬ 𝑎 < 𝑦 ↔ ¬ 𝑥 < 𝑦))
43ralbidv 2373 . . . . . 6 (𝑎 = 𝑥 → (∀𝑦𝐴 ¬ 𝑎 < 𝑦 ↔ ∀𝑦𝐴 ¬ 𝑥 < 𝑦))
5 breq2 3809 . . . . . . . 8 (𝑎 = 𝑥 → (𝑦 < 𝑎𝑦 < 𝑥))
65imbi1d 229 . . . . . . 7 (𝑎 = 𝑥 → ((𝑦 < 𝑎 → ∃𝑧𝐴 𝑦 < 𝑧) ↔ (𝑦 < 𝑥 → ∃𝑧𝐴 𝑦 < 𝑧)))
76ralbidv 2373 . . . . . 6 (𝑎 = 𝑥 → (∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧𝐴 𝑦 < 𝑧) ↔ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧𝐴 𝑦 < 𝑧)))
84, 7anbi12d 457 . . . . 5 (𝑎 = 𝑥 → ((∀𝑦𝐴 ¬ 𝑎 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧𝐴 𝑦 < 𝑧)) ↔ (∀𝑦𝐴 ¬ 𝑥 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧𝐴 𝑦 < 𝑧))))
98cbvrexv 2583 . . . 4 (∃𝑎 ∈ ℝ (∀𝑦𝐴 ¬ 𝑎 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧𝐴 𝑦 < 𝑧)) ↔ ∃𝑥 ∈ ℝ (∀𝑦𝐴 ¬ 𝑥 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧𝐴 𝑦 < 𝑧)))
101, 9sylibr 132 . . 3 (𝜑 → ∃𝑎 ∈ ℝ (∀𝑦𝐴 ¬ 𝑎 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧𝐴 𝑦 < 𝑧)))
11 breq2 3809 . . . . . . 7 (𝑏 = 𝑦 → (𝑎 < 𝑏𝑎 < 𝑦))
1211notbid 625 . . . . . 6 (𝑏 = 𝑦 → (¬ 𝑎 < 𝑏 ↔ ¬ 𝑎 < 𝑦))
1312cbvralv 2582 . . . . 5 (∀𝑏𝐴 ¬ 𝑎 < 𝑏 ↔ ∀𝑦𝐴 ¬ 𝑎 < 𝑦)
14 breq2 3809 . . . . . . . . 9 (𝑐 = 𝑧 → (𝑏 < 𝑐𝑏 < 𝑧))
1514cbvrexv 2583 . . . . . . . 8 (∃𝑐𝐴 𝑏 < 𝑐 ↔ ∃𝑧𝐴 𝑏 < 𝑧)
1615imbi2i 224 . . . . . . 7 ((𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐) ↔ (𝑏 < 𝑎 → ∃𝑧𝐴 𝑏 < 𝑧))
1716ralbii 2377 . . . . . 6 (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐) ↔ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑧𝐴 𝑏 < 𝑧))
18 breq1 3808 . . . . . . . 8 (𝑏 = 𝑦 → (𝑏 < 𝑎𝑦 < 𝑎))
19 breq1 3808 . . . . . . . . 9 (𝑏 = 𝑦 → (𝑏 < 𝑧𝑦 < 𝑧))
2019rexbidv 2374 . . . . . . . 8 (𝑏 = 𝑦 → (∃𝑧𝐴 𝑏 < 𝑧 ↔ ∃𝑧𝐴 𝑦 < 𝑧))
2118, 20imbi12d 232 . . . . . . 7 (𝑏 = 𝑦 → ((𝑏 < 𝑎 → ∃𝑧𝐴 𝑏 < 𝑧) ↔ (𝑦 < 𝑎 → ∃𝑧𝐴 𝑦 < 𝑧)))
2221cbvralv 2582 . . . . . 6 (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑧𝐴 𝑏 < 𝑧) ↔ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧𝐴 𝑦 < 𝑧))
2317, 22bitri 182 . . . . 5 (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐) ↔ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧𝐴 𝑦 < 𝑧))
2413, 23anbi12i 448 . . . 4 ((∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ↔ (∀𝑦𝐴 ¬ 𝑎 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧𝐴 𝑦 < 𝑧)))
2524rexbii 2378 . . 3 (∃𝑎 ∈ ℝ (∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ↔ ∃𝑎 ∈ ℝ (∀𝑦𝐴 ¬ 𝑎 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧𝐴 𝑦 < 𝑧)))
2610, 25sylibr 132 . 2 (𝜑 → ∃𝑎 ∈ ℝ (∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)))
27 renegcl 7488 . . . . . 6 (𝑎 ∈ ℝ → -𝑎 ∈ ℝ)
2827ad2antlr 473 . . . . 5 (((𝜑𝑎 ∈ ℝ) ∧ (∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐))) → -𝑎 ∈ ℝ)
29 simplr 497 . . . . . 6 (((𝜑𝑎 ∈ ℝ) ∧ (∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐))) → 𝑎 ∈ ℝ)
30 simprl 498 . . . . . 6 (((𝜑𝑎 ∈ ℝ) ∧ (∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐))) → ∀𝑏𝐴 ¬ 𝑎 < 𝑏)
31 elrabi 2754 . . . . . . . . . . . 12 (𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} → 𝑦 ∈ ℝ)
32 negeq 7420 . . . . . . . . . . . . . . 15 (𝑤 = 𝑦 → -𝑤 = -𝑦)
3332eleq1d 2151 . . . . . . . . . . . . . 14 (𝑤 = 𝑦 → (-𝑤𝐴 ↔ -𝑦𝐴))
3433elrab3 2758 . . . . . . . . . . . . 13 (𝑦 ∈ ℝ → (𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ↔ -𝑦𝐴))
3534biimpd 142 . . . . . . . . . . . 12 (𝑦 ∈ ℝ → (𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} → -𝑦𝐴))
3631, 35mpcom 36 . . . . . . . . . . 11 (𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} → -𝑦𝐴)
37 breq2 3809 . . . . . . . . . . . . 13 (𝑏 = -𝑦 → (𝑎 < 𝑏𝑎 < -𝑦))
3837notbid 625 . . . . . . . . . . . 12 (𝑏 = -𝑦 → (¬ 𝑎 < 𝑏 ↔ ¬ 𝑎 < -𝑦))
3938rspcv 2706 . . . . . . . . . . 11 (-𝑦𝐴 → (∀𝑏𝐴 ¬ 𝑎 < 𝑏 → ¬ 𝑎 < -𝑦))
4036, 39syl 14 . . . . . . . . . 10 (𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} → (∀𝑏𝐴 ¬ 𝑎 < 𝑏 → ¬ 𝑎 < -𝑦))
4140adantr 270 . . . . . . . . 9 ((𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ∧ 𝑎 ∈ ℝ) → (∀𝑏𝐴 ¬ 𝑎 < 𝑏 → ¬ 𝑎 < -𝑦))
42 ltnegcon2 7687 . . . . . . . . . . 11 ((𝑦 ∈ ℝ ∧ 𝑎 ∈ ℝ) → (𝑦 < -𝑎𝑎 < -𝑦))
4342notbid 625 . . . . . . . . . 10 ((𝑦 ∈ ℝ ∧ 𝑎 ∈ ℝ) → (¬ 𝑦 < -𝑎 ↔ ¬ 𝑎 < -𝑦))
4431, 43sylan 277 . . . . . . . . 9 ((𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ∧ 𝑎 ∈ ℝ) → (¬ 𝑦 < -𝑎 ↔ ¬ 𝑎 < -𝑦))
4541, 44sylibrd 167 . . . . . . . 8 ((𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ∧ 𝑎 ∈ ℝ) → (∀𝑏𝐴 ¬ 𝑎 < 𝑏 → ¬ 𝑦 < -𝑎))
4645ancoms 264 . . . . . . 7 ((𝑎 ∈ ℝ ∧ 𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}) → (∀𝑏𝐴 ¬ 𝑎 < 𝑏 → ¬ 𝑦 < -𝑎))
4746ralrimdva 2446 . . . . . 6 (𝑎 ∈ ℝ → (∀𝑏𝐴 ¬ 𝑎 < 𝑏 → ∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < -𝑎))
4829, 30, 47sylc 61 . . . . 5 (((𝜑𝑎 ∈ ℝ) ∧ (∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐))) → ∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < -𝑎)
49 nfv 1462 . . . . . . . . . . . 12 𝑐(𝜑𝑎 ∈ ℝ)
50 nfcv 2223 . . . . . . . . . . . . 13 𝑐
51 nfv 1462 . . . . . . . . . . . . . 14 𝑐 𝑏 < 𝑎
52 nfre1 2412 . . . . . . . . . . . . . 14 𝑐𝑐𝐴 𝑏 < 𝑐
5351, 52nfim 1505 . . . . . . . . . . . . 13 𝑐(𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)
5450, 53nfralya 2409 . . . . . . . . . . . 12 𝑐𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)
5549, 54nfan 1498 . . . . . . . . . . 11 𝑐((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐))
56 nfv 1462 . . . . . . . . . . 11 𝑐 𝑦 ∈ ℝ
5755, 56nfan 1498 . . . . . . . . . 10 𝑐(((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ)
58 nfv 1462 . . . . . . . . . 10 𝑐-𝑎 < 𝑦
5957, 58nfan 1498 . . . . . . . . 9 𝑐((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦)
60 simplr 497 . . . . . . . . . . . . 13 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → 𝑐𝐴)
61 supinfneg.ss . . . . . . . . . . . . . . 15 (𝜑𝐴 ⊆ ℝ)
6261sseld 3007 . . . . . . . . . . . . . 14 (𝜑 → (𝑐𝐴𝑐 ∈ ℝ))
6362ad6antr 482 . . . . . . . . . . . . 13 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → (𝑐𝐴𝑐 ∈ ℝ))
6460, 63mpd 13 . . . . . . . . . . . 12 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → 𝑐 ∈ ℝ)
6564renegcld 7603 . . . . . . . . . . 11 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → -𝑐 ∈ ℝ)
6664recnd 7261 . . . . . . . . . . . . 13 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → 𝑐 ∈ ℂ)
6766negnegd 7529 . . . . . . . . . . . 12 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → --𝑐 = 𝑐)
6867, 60eqeltrd 2159 . . . . . . . . . . 11 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → --𝑐𝐴)
69 negeq 7420 . . . . . . . . . . . . 13 (𝑤 = -𝑐 → -𝑤 = --𝑐)
7069eleq1d 2151 . . . . . . . . . . . 12 (𝑤 = -𝑐 → (-𝑤𝐴 ↔ --𝑐𝐴))
7170elrab 2757 . . . . . . . . . . 11 (-𝑐 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ↔ (-𝑐 ∈ ℝ ∧ --𝑐𝐴))
7265, 68, 71sylanbrc 408 . . . . . . . . . 10 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → -𝑐 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴})
73 simp-4r 509 . . . . . . . . . . 11 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → 𝑦 ∈ ℝ)
74 simpr 108 . . . . . . . . . . 11 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → -𝑦 < 𝑐)
7573, 64, 74ltnegcon1d 7744 . . . . . . . . . 10 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → -𝑐 < 𝑦)
76 breq1 3808 . . . . . . . . . . 11 (𝑧 = -𝑐 → (𝑧 < 𝑦 ↔ -𝑐 < 𝑦))
7776rspcev 2710 . . . . . . . . . 10 ((-𝑐 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ∧ -𝑐 < 𝑦) → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦)
7872, 75, 77syl2anc 403 . . . . . . . . 9 (((((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐𝐴) ∧ -𝑦 < 𝑐) → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦)
79 simpllr 501 . . . . . . . . . . 11 ((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) → 𝑎 ∈ ℝ)
80 simpr 108 . . . . . . . . . . 11 ((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) → 𝑦 ∈ ℝ)
81 simplr 497 . . . . . . . . . . 11 ((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) → ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐))
8279, 80, 81jca31 302 . . . . . . . . . 10 ((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) → ((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)))
83 ltnegcon1 7686 . . . . . . . . . . . . 13 ((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) → (-𝑎 < 𝑦 ↔ -𝑦 < 𝑎))
8483adantr 270 . . . . . . . . . . . 12 (((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) → (-𝑎 < 𝑦 ↔ -𝑦 < 𝑎))
85 renegcl 7488 . . . . . . . . . . . . . . 15 (𝑦 ∈ ℝ → -𝑦 ∈ ℝ)
86 breq1 3808 . . . . . . . . . . . . . . . . 17 (𝑏 = -𝑦 → (𝑏 < 𝑎 ↔ -𝑦 < 𝑎))
87 breq1 3808 . . . . . . . . . . . . . . . . . 18 (𝑏 = -𝑦 → (𝑏 < 𝑐 ↔ -𝑦 < 𝑐))
8887rexbidv 2374 . . . . . . . . . . . . . . . . 17 (𝑏 = -𝑦 → (∃𝑐𝐴 𝑏 < 𝑐 ↔ ∃𝑐𝐴 -𝑦 < 𝑐))
8986, 88imbi12d 232 . . . . . . . . . . . . . . . 16 (𝑏 = -𝑦 → ((𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐) ↔ (-𝑦 < 𝑎 → ∃𝑐𝐴 -𝑦 < 𝑐)))
9089rspcv 2706 . . . . . . . . . . . . . . 15 (-𝑦 ∈ ℝ → (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐) → (-𝑦 < 𝑎 → ∃𝑐𝐴 -𝑦 < 𝑐)))
9185, 90syl 14 . . . . . . . . . . . . . 14 (𝑦 ∈ ℝ → (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐) → (-𝑦 < 𝑎 → ∃𝑐𝐴 -𝑦 < 𝑐)))
9291adantl 271 . . . . . . . . . . . . 13 ((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) → (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐) → (-𝑦 < 𝑎 → ∃𝑐𝐴 -𝑦 < 𝑐)))
9392imp 122 . . . . . . . . . . . 12 (((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) → (-𝑦 < 𝑎 → ∃𝑐𝐴 -𝑦 < 𝑐))
9484, 93sylbid 148 . . . . . . . . . . 11 (((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) → (-𝑎 < 𝑦 → ∃𝑐𝐴 -𝑦 < 𝑐))
9594imp 122 . . . . . . . . . 10 ((((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ -𝑎 < 𝑦) → ∃𝑐𝐴 -𝑦 < 𝑐)
9682, 95sylan 277 . . . . . . . . 9 (((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) → ∃𝑐𝐴 -𝑦 < 𝑐)
9759, 78, 96r19.29af 2502 . . . . . . . 8 (((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦)
9897ex 113 . . . . . . 7 ((((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) → (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦))
9998ralrimiva 2439 . . . . . 6 (((𝜑𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) → ∀𝑦 ∈ ℝ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦))
10099adantrl 462 . . . . 5 (((𝜑𝑎 ∈ ℝ) ∧ (∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐))) → ∀𝑦 ∈ ℝ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦))
101 breq2 3809 . . . . . . . . 9 (𝑥 = -𝑎 → (𝑦 < 𝑥𝑦 < -𝑎))
102101notbid 625 . . . . . . . 8 (𝑥 = -𝑎 → (¬ 𝑦 < 𝑥 ↔ ¬ 𝑦 < -𝑎))
103102ralbidv 2373 . . . . . . 7 (𝑥 = -𝑎 → (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < 𝑥 ↔ ∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < -𝑎))
104 breq1 3808 . . . . . . . . 9 (𝑥 = -𝑎 → (𝑥 < 𝑦 ↔ -𝑎 < 𝑦))
105104imbi1d 229 . . . . . . . 8 (𝑥 = -𝑎 → ((𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦) ↔ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦)))
106105ralbidv 2373 . . . . . . 7 (𝑥 = -𝑎 → (∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦) ↔ ∀𝑦 ∈ ℝ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦)))
107103, 106anbi12d 457 . . . . . 6 (𝑥 = -𝑎 → ((∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦)) ↔ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < -𝑎 ∧ ∀𝑦 ∈ ℝ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦))))
108107rspcev 2710 . . . . 5 ((-𝑎 ∈ ℝ ∧ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < -𝑎 ∧ ∀𝑦 ∈ ℝ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦))) → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦)))
10928, 48, 100, 108syl12anc 1168 . . . 4 (((𝜑𝑎 ∈ ℝ) ∧ (∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐))) → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦)))
110109ex 113 . . 3 ((𝜑𝑎 ∈ ℝ) → ((∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦))))
111110rexlimdva 2482 . 2 (𝜑 → (∃𝑎 ∈ ℝ (∀𝑏𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐𝐴 𝑏 < 𝑐)) → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦))))
11226, 111mpd 13 1 (𝜑 → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤𝐴}𝑧 < 𝑦)))
 Colors of variables: wff set class Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 102   ↔ wb 103   = wceq 1285   ∈ wcel 1434  ∀wral 2353  ∃wrex 2354  {crab 2357   ⊆ wss 2982   class class class wbr 3805  ℝcr 7094   < clt 7267  -cneg 7399 This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-in1 577  ax-in2 578  ax-io 663  ax-5 1377  ax-7 1378  ax-gen 1379  ax-ie1 1423  ax-ie2 1424  ax-8 1436  ax-10 1437  ax-11 1438  ax-i12 1439  ax-bndl 1440  ax-4 1441  ax-13 1445  ax-14 1446  ax-17 1460  ax-i9 1464  ax-ial 1468  ax-i5r 1469  ax-ext 2065  ax-sep 3916  ax-pow 3968  ax-pr 3992  ax-un 4216  ax-setind 4308  ax-cnex 7181  ax-resscn 7182  ax-1cn 7183  ax-1re 7184  ax-icn 7185  ax-addcl 7186  ax-addrcl 7187  ax-mulcl 7188  ax-addcom 7190  ax-addass 7192  ax-distr 7194  ax-i2m1 7195  ax-0id 7198  ax-rnegex 7199  ax-cnre 7201  ax-pre-ltadd 7206 This theorem depends on definitions:  df-bi 115  df-3an 922  df-tru 1288  df-fal 1291  df-nf 1391  df-sb 1688  df-eu 1946  df-mo 1947  df-clab 2070  df-cleq 2076  df-clel 2079  df-nfc 2212  df-ne 2250  df-nel 2345  df-ral 2358  df-rex 2359  df-reu 2360  df-rab 2362  df-v 2612  df-sbc 2825  df-dif 2984  df-un 2986  df-in 2988  df-ss 2995  df-pw 3402  df-sn 3422  df-pr 3423  df-op 3425  df-uni 3622  df-br 3806  df-opab 3860  df-id 4076  df-xp 4397  df-rel 4398  df-cnv 4399  df-co 4400  df-dm 4401  df-iota 4917  df-fun 4954  df-fv 4960  df-riota 5519  df-ov 5566  df-oprab 5567  df-mpt2 5568  df-pnf 7269  df-mnf 7270  df-ltxr 7272  df-sub 7400  df-neg 7401 This theorem is referenced by:  supminfex  8818  infssuzex  10552
 Copyright terms: Public domain W3C validator