Theorem supinfneg 9974

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 9992. (Contributed by Jim Kingdon, 15-Jan-2022.)

Hypotheses

Ref	Expression
supinfneg.ex	⊢ (𝜑 → ∃𝑥 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑥 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)))
supinfneg.ss	⊢ (𝜑 → 𝐴 ⊆ ℝ)

Assertion

Ref	Expression
supinfneg	⊢ (𝜑 → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}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.

Step	Hyp	Ref	Expression
1		supinfneg.ex	. . . 4 ⊢ (𝜑 → ∃𝑥 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑥 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)))
2		breq1 4128	. . . . . . . 8 ⊢ (𝑎 = 𝑥 → (𝑎 < 𝑦 ↔ 𝑥 < 𝑦))
3	2	notbid 677	. . . . . . 7 ⊢ (𝑎 = 𝑥 → (¬ 𝑎 < 𝑦 ↔ ¬ 𝑥 < 𝑦))
4	3	ralbidv 2550	. . . . . 6 ⊢ (𝑎 = 𝑥 → (∀𝑦 ∈ 𝐴 ¬ 𝑎 < 𝑦 ↔ ∀𝑦 ∈ 𝐴 ¬ 𝑥 < 𝑦))
5		breq2 4129	. . . . . . . 8 ⊢ (𝑎 = 𝑥 → (𝑦 < 𝑎 ↔ 𝑦 < 𝑥))
6	5	imbi1d 231	. . . . . . 7 ⊢ (𝑎 = 𝑥 → ((𝑦 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧) ↔ (𝑦 < 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)))
7	6	ralbidv 2550	. . . . . 6 ⊢ (𝑎 = 𝑥 → (∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧) ↔ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)))
8	4, 7	anbi12d 477	. . . . 5 ⊢ (𝑎 = 𝑥 → ((∀𝑦 ∈ 𝐴 ¬ 𝑎 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)) ↔ (∀𝑦 ∈ 𝐴 ¬ 𝑥 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧))))
9	8	cbvrexv 2787	. . . 4 ⊢ (∃𝑎 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑎 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)) ↔ ∃𝑥 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑥 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)))
10	1, 9	sylibr 134	. . 3 ⊢ (𝜑 → ∃𝑎 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑎 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)))
11		breq2 4129	. . . . . . 7 ⊢ (𝑏 = 𝑦 → (𝑎 < 𝑏 ↔ 𝑎 < 𝑦))
12	11	notbid 677	. . . . . 6 ⊢ (𝑏 = 𝑦 → (¬ 𝑎 < 𝑏 ↔ ¬ 𝑎 < 𝑦))
13	12	cbvralv 2786	. . . . 5 ⊢ (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ↔ ∀𝑦 ∈ 𝐴 ¬ 𝑎 < 𝑦)
14		breq2 4129	. . . . . . . . 9 ⊢ (𝑐 = 𝑧 → (𝑏 < 𝑐 ↔ 𝑏 < 𝑧))
15	14	cbvrexv 2787	. . . . . . . 8 ⊢ (∃𝑐 ∈ 𝐴 𝑏 < 𝑐 ↔ ∃𝑧 ∈ 𝐴 𝑏 < 𝑧)
16	15	imbi2i 226	. . . . . . 7 ⊢ ((𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐) ↔ (𝑏 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑏 < 𝑧))
17	16	ralbii 2556	. . . . . 6 ⊢ (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐) ↔ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑏 < 𝑧))
18		breq1 4128	. . . . . . . 8 ⊢ (𝑏 = 𝑦 → (𝑏 < 𝑎 ↔ 𝑦 < 𝑎))
19		breq1 4128	. . . . . . . . 9 ⊢ (𝑏 = 𝑦 → (𝑏 < 𝑧 ↔ 𝑦 < 𝑧))
20	19	rexbidv 2551	. . . . . . . 8 ⊢ (𝑏 = 𝑦 → (∃𝑧 ∈ 𝐴 𝑏 < 𝑧 ↔ ∃𝑧 ∈ 𝐴 𝑦 < 𝑧))
21	18, 20	imbi12d 234	. . . . . . 7 ⊢ (𝑏 = 𝑦 → ((𝑏 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑏 < 𝑧) ↔ (𝑦 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)))
22	21	cbvralv 2786	. . . . . 6 ⊢ (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑏 < 𝑧) ↔ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧))
23	17, 22	bitri 184	. . . . 5 ⊢ (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐) ↔ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧))
24	13, 23	anbi12i 464	. . . 4 ⊢ ((∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ↔ (∀𝑦 ∈ 𝐴 ¬ 𝑎 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)))
25	24	rexbii 2557	. . 3 ⊢ (∃𝑎 ∈ ℝ (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ↔ ∃𝑎 ∈ ℝ (∀𝑦 ∈ 𝐴 ¬ 𝑎 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑎 → ∃𝑧 ∈ 𝐴 𝑦 < 𝑧)))
26	10, 25	sylibr 134	. 2 ⊢ (𝜑 → ∃𝑎 ∈ ℝ (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)))
27		renegcl 8577	. . . . . 6 ⊢ (𝑎 ∈ ℝ → -𝑎 ∈ ℝ)
28	27	ad2antlr 493	. . . . 5 ⊢ (((𝜑 ∧ 𝑎 ∈ ℝ) ∧ (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐))) → -𝑎 ∈ ℝ)
29		simplr 533	. . . . . 6 ⊢ (((𝜑 ∧ 𝑎 ∈ ℝ) ∧ (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐))) → 𝑎 ∈ ℝ)
30		simprl 535	. . . . . 6 ⊢ (((𝜑 ∧ 𝑎 ∈ ℝ) ∧ (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐))) → ∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏)
31		elrabi 2979	. . . . . . . . . . . 12 ⊢ (𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} → 𝑦 ∈ ℝ)
32		negeq 8509	. . . . . . . . . . . . . . 15 ⊢ (𝑤 = 𝑦 → -𝑤 = -𝑦)
33	32	eleq1d 2307	. . . . . . . . . . . . . 14 ⊢ (𝑤 = 𝑦 → (-𝑤 ∈ 𝐴 ↔ -𝑦 ∈ 𝐴))
34	33	elrab3 2983	. . . . . . . . . . . . 13 ⊢ (𝑦 ∈ ℝ → (𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ↔ -𝑦 ∈ 𝐴))
35	34	biimpd 144	. . . . . . . . . . . 12 ⊢ (𝑦 ∈ ℝ → (𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} → -𝑦 ∈ 𝐴))
36	31, 35	mpcom 36	. . . . . . . . . . 11 ⊢ (𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} → -𝑦 ∈ 𝐴)
37		breq2 4129	. . . . . . . . . . . . 13 ⊢ (𝑏 = -𝑦 → (𝑎 < 𝑏 ↔ 𝑎 < -𝑦))
38	37	notbid 677	. . . . . . . . . . . 12 ⊢ (𝑏 = -𝑦 → (¬ 𝑎 < 𝑏 ↔ ¬ 𝑎 < -𝑦))
39	38	rspcv 2925	. . . . . . . . . . 11 ⊢ (-𝑦 ∈ 𝐴 → (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 → ¬ 𝑎 < -𝑦))
40	36, 39	syl 14	. . . . . . . . . 10 ⊢ (𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} → (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 → ¬ 𝑎 < -𝑦))
41	40	adantr 276	. . . . . . . . 9 ⊢ ((𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ∧ 𝑎 ∈ ℝ) → (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 → ¬ 𝑎 < -𝑦))
42		ltnegcon2 8782	. . . . . . . . . . 11 ⊢ ((𝑦 ∈ ℝ ∧ 𝑎 ∈ ℝ) → (𝑦 < -𝑎 ↔ 𝑎 < -𝑦))
43	42	notbid 677	. . . . . . . . . 10 ⊢ ((𝑦 ∈ ℝ ∧ 𝑎 ∈ ℝ) → (¬ 𝑦 < -𝑎 ↔ ¬ 𝑎 < -𝑦))
44	31, 43	sylan 283	. . . . . . . . 9 ⊢ ((𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ∧ 𝑎 ∈ ℝ) → (¬ 𝑦 < -𝑎 ↔ ¬ 𝑎 < -𝑦))
45	41, 44	sylibrd 169	. . . . . . . 8 ⊢ ((𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ∧ 𝑎 ∈ ℝ) → (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 → ¬ 𝑦 < -𝑎))
46	45	ancoms 268	. . . . . . 7 ⊢ ((𝑎 ∈ ℝ ∧ 𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}) → (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 → ¬ 𝑦 < -𝑎))
47	46	ralrimdva 2630	. . . . . 6 ⊢ (𝑎 ∈ ℝ → (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 → ∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < -𝑎))
48	29, 30, 47	sylc 62	. . . . 5 ⊢ (((𝜑 ∧ 𝑎 ∈ ℝ) ∧ (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐))) → ∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < -𝑎)
49		nfv 1581	. . . . . . . . . . . 12 ⊢ Ⅎ𝑐(𝜑 ∧ 𝑎 ∈ ℝ)
50		nfcv 2392	. . . . . . . . . . . . 13 ⊢ Ⅎ𝑐ℝ
51		nfv 1581	. . . . . . . . . . . . . 14 ⊢ Ⅎ𝑐 𝑏 < 𝑎
52		nfre1 2593	. . . . . . . . . . . . . 14 ⊢ Ⅎ𝑐∃𝑐 ∈ 𝐴 𝑏 < 𝑐
53	51, 52	nfim 1625	. . . . . . . . . . . . 13 ⊢ Ⅎ𝑐(𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)
54	50, 53	nfralya 2590	. . . . . . . . . . . 12 ⊢ Ⅎ𝑐∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)
55	49, 54	nfan 1618	. . . . . . . . . . 11 ⊢ Ⅎ𝑐((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐))
56		nfv 1581	. . . . . . . . . . 11 ⊢ Ⅎ𝑐 𝑦 ∈ ℝ
57	55, 56	nfan 1618	. . . . . . . . . 10 ⊢ Ⅎ𝑐(((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ)
58		nfv 1581	. . . . . . . . . 10 ⊢ Ⅎ𝑐-𝑎 < 𝑦
59	57, 58	nfan 1618	. . . . . . . . 9 ⊢ Ⅎ𝑐((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦)
60		simplr 533	. . . . . . . . . . . . 13 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → 𝑐 ∈ 𝐴)
61		supinfneg.ss	. . . . . . . . . . . . . . 15 ⊢ (𝜑 → 𝐴 ⊆ ℝ)
62	61	sseld 3247	. . . . . . . . . . . . . 14 ⊢ (𝜑 → (𝑐 ∈ 𝐴 → 𝑐 ∈ ℝ))
63	62	ad6antr 502	. . . . . . . . . . . . 13 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → (𝑐 ∈ 𝐴 → 𝑐 ∈ ℝ))
64	60, 63	mpd 13	. . . . . . . . . . . 12 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → 𝑐 ∈ ℝ)
65	64	renegcld 8697	. . . . . . . . . . 11 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → -𝑐 ∈ ℝ)
66	64	recnd 8344	. . . . . . . . . . . . 13 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → 𝑐 ∈ ℂ)
67	66	negnegd 8618	. . . . . . . . . . . 12 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → --𝑐 = 𝑐)
68	67, 60	eqeltrd 2315	. . . . . . . . . . 11 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → --𝑐 ∈ 𝐴)
69		negeq 8509	. . . . . . . . . . . . 13 ⊢ (𝑤 = -𝑐 → -𝑤 = --𝑐)
70	69	eleq1d 2307	. . . . . . . . . . . 12 ⊢ (𝑤 = -𝑐 → (-𝑤 ∈ 𝐴 ↔ --𝑐 ∈ 𝐴))
71	70	elrab 2982	. . . . . . . . . . 11 ⊢ (-𝑐 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ↔ (-𝑐 ∈ ℝ ∧ --𝑐 ∈ 𝐴))
72	65, 68, 71	sylanbrc 421	. . . . . . . . . 10 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → -𝑐 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴})
73		simp-4r 548	. . . . . . . . . . 11 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → 𝑦 ∈ ℝ)
74		simpr 110	. . . . . . . . . . 11 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → -𝑦 < 𝑐)
75	73, 64, 74	ltnegcon1d 8843	. . . . . . . . . 10 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → -𝑐 < 𝑦)
76		breq1 4128	. . . . . . . . . . 11 ⊢ (𝑧 = -𝑐 → (𝑧 < 𝑦 ↔ -𝑐 < 𝑦))
77	76	rspcev 2929	. . . . . . . . . 10 ⊢ ((-𝑐 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ∧ -𝑐 < 𝑦) → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦)
78	72, 75, 77	syl2anc 415	. . . . . . . . 9 ⊢ (((((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) ∧ 𝑐 ∈ 𝐴) ∧ -𝑦 < 𝑐) → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦)
79		simpllr 540	. . . . . . . . . . 11 ⊢ ((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) → 𝑎 ∈ ℝ)
80		simpr 110	. . . . . . . . . . 11 ⊢ ((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) → 𝑦 ∈ ℝ)
81		simplr 533	. . . . . . . . . . 11 ⊢ ((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) → ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐))
82	79, 80, 81	jca31 309	. . . . . . . . . 10 ⊢ ((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) → ((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)))
83		ltnegcon1 8781	. . . . . . . . . . . . 13 ⊢ ((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) → (-𝑎 < 𝑦 ↔ -𝑦 < 𝑎))
84	83	adantr 276	. . . . . . . . . . . 12 ⊢ (((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) → (-𝑎 < 𝑦 ↔ -𝑦 < 𝑎))
85		renegcl 8577	. . . . . . . . . . . . . . 15 ⊢ (𝑦 ∈ ℝ → -𝑦 ∈ ℝ)
86		breq1 4128	. . . . . . . . . . . . . . . . 17 ⊢ (𝑏 = -𝑦 → (𝑏 < 𝑎 ↔ -𝑦 < 𝑎))
87		breq1 4128	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑏 = -𝑦 → (𝑏 < 𝑐 ↔ -𝑦 < 𝑐))
88	87	rexbidv 2551	. . . . . . . . . . . . . . . . 17 ⊢ (𝑏 = -𝑦 → (∃𝑐 ∈ 𝐴 𝑏 < 𝑐 ↔ ∃𝑐 ∈ 𝐴 -𝑦 < 𝑐))
89	86, 88	imbi12d 234	. . . . . . . . . . . . . . . 16 ⊢ (𝑏 = -𝑦 → ((𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐) ↔ (-𝑦 < 𝑎 → ∃𝑐 ∈ 𝐴 -𝑦 < 𝑐)))
90	89	rspcv 2925	. . . . . . . . . . . . . . 15 ⊢ (-𝑦 ∈ ℝ → (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐) → (-𝑦 < 𝑎 → ∃𝑐 ∈ 𝐴 -𝑦 < 𝑐)))
91	85, 90	syl 14	. . . . . . . . . . . . . 14 ⊢ (𝑦 ∈ ℝ → (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐) → (-𝑦 < 𝑎 → ∃𝑐 ∈ 𝐴 -𝑦 < 𝑐)))
92	91	adantl 277	. . . . . . . . . . . . 13 ⊢ ((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) → (∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐) → (-𝑦 < 𝑎 → ∃𝑐 ∈ 𝐴 -𝑦 < 𝑐)))
93	92	imp 124	. . . . . . . . . . . 12 ⊢ (((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) → (-𝑦 < 𝑎 → ∃𝑐 ∈ 𝐴 -𝑦 < 𝑐))
94	84, 93	sylbid 150	. . . . . . . . . . 11 ⊢ (((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) → (-𝑎 < 𝑦 → ∃𝑐 ∈ 𝐴 -𝑦 < 𝑐))
95	94	imp 124	. . . . . . . . . 10 ⊢ ((((𝑎 ∈ ℝ ∧ 𝑦 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ -𝑎 < 𝑦) → ∃𝑐 ∈ 𝐴 -𝑦 < 𝑐)
96	82, 95	sylan 283	. . . . . . . . 9 ⊢ (((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) → ∃𝑐 ∈ 𝐴 -𝑦 < 𝑐)
97	59, 78, 96	r19.29af 2692	. . . . . . . 8 ⊢ (((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) ∧ -𝑎 < 𝑦) → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦)
98	97	ex 115	. . . . . . 7 ⊢ ((((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) ∧ 𝑦 ∈ ℝ) → (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦))
99	98	ralrimiva 2623	. . . . . 6 ⊢ (((𝜑 ∧ 𝑎 ∈ ℝ) ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) → ∀𝑦 ∈ ℝ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦))
100	99	adantrl 482	. . . . 5 ⊢ (((𝜑 ∧ 𝑎 ∈ ℝ) ∧ (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐))) → ∀𝑦 ∈ ℝ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦))
101		breq2 4129	. . . . . . . . 9 ⊢ (𝑥 = -𝑎 → (𝑦 < 𝑥 ↔ 𝑦 < -𝑎))
102	101	notbid 677	. . . . . . . 8 ⊢ (𝑥 = -𝑎 → (¬ 𝑦 < 𝑥 ↔ ¬ 𝑦 < -𝑎))
103	102	ralbidv 2550	. . . . . . 7 ⊢ (𝑥 = -𝑎 → (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < 𝑥 ↔ ∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < -𝑎))
104		breq1 4128	. . . . . . . . 9 ⊢ (𝑥 = -𝑎 → (𝑥 < 𝑦 ↔ -𝑎 < 𝑦))
105	104	imbi1d 231	. . . . . . . 8 ⊢ (𝑥 = -𝑎 → ((𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦) ↔ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦)))
106	105	ralbidv 2550	. . . . . . 7 ⊢ (𝑥 = -𝑎 → (∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦) ↔ ∀𝑦 ∈ ℝ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦)))
107	103, 106	anbi12d 477	. . . . . 6 ⊢ (𝑥 = -𝑎 → ((∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦)) ↔ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < -𝑎 ∧ ∀𝑦 ∈ ℝ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦))))
108	107	rspcev 2929	. . . . 5 ⊢ ((-𝑎 ∈ ℝ ∧ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < -𝑎 ∧ ∀𝑦 ∈ ℝ (-𝑎 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦))) → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦)))
109	28, 48, 100, 108	syl12anc 1276	. . . 4 ⊢ (((𝜑 ∧ 𝑎 ∈ ℝ) ∧ (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐))) → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦)))
110	109	ex 115	. . 3 ⊢ ((𝜑 ∧ 𝑎 ∈ ℝ) → ((∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦))))
111	110	rexlimdva 2668	. 2 ⊢ (𝜑 → (∃𝑎 ∈ ℝ (∀𝑏 ∈ 𝐴 ¬ 𝑎 < 𝑏 ∧ ∀𝑏 ∈ ℝ (𝑏 < 𝑎 → ∃𝑐 ∈ 𝐴 𝑏 < 𝑐)) → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦))))
112	26, 111	mpd 13	1 ⊢ (𝜑 → ∃𝑥 ∈ ℝ (∀𝑦 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴} ¬ 𝑦 < 𝑥 ∧ ∀𝑦 ∈ ℝ (𝑥 < 𝑦 → ∃𝑧 ∈ {𝑤 ∈ ℝ ∣ -𝑤 ∈ 𝐴}𝑧 < 𝑦)))

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 104   ↔ wb 105   = wceq 1402   ∈ wcel 2209  ∀wral 2528  ∃wrex 2529  {crab 2532   ⊆ wss 3220   class class class wbr 4125  ℝcr 8168   < clt 8350  -cneg 8488

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4244  ax-pow 4306  ax-pr 4341  ax-un 4573  ax-setind 4679  ax-cnex 8260  ax-resscn 8261  ax-1cn 8262  ax-1re 8263  ax-icn 8264  ax-addcl 8265  ax-addrcl 8266  ax-mulcl 8267  ax-addcom 8269  ax-addass 8271  ax-distr 8273  ax-i2m1 8274  ax-0id 8277  ax-rnegex 8278  ax-cnre 8280  ax-pre-ltadd 8285

This theorem depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-nel 2516  df-ral 2533  df-rex 2534  df-reu 2535  df-rab 2537  df-v 2823  df-sbc 3052  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-pw 3687  df-sn 3711  df-pr 3712  df-op 3714  df-uni 3931  df-br 4126  df-opab 4188  df-id 4433  df-xp 4775  df-rel 4776  df-cnv 4777  df-co 4778  df-dm 4779  df-iota 5332  df-fun 5374  df-fv 5380  df-riota 6028  df-ov 6078  df-oprab 6079  df-mpo 6080  df-pnf 8352  df-mnf 8353  df-ltxr 8355  df-sub 8489  df-neg 8490

This theorem is referenced by:  supminfex  9976  infssuzex  10644