Theorem dedekindicclemub 15728

Description: Lemma for dedekindicc 15734. The lower cut has an upper bound. (Contributed by Jim Kingdon, 15-Feb-2024.)

Hypotheses

Ref	Expression
dedekindicc.a	⊢ (𝜑 → 𝐴 ∈ ℝ)
dedekindicc.b	⊢ (𝜑 → 𝐵 ∈ ℝ)
dedekindicc.lss	⊢ (𝜑 → 𝐿 ⊆ (𝐴[,]𝐵))
dedekindicc.uss	⊢ (𝜑 → 𝑈 ⊆ (𝐴[,]𝐵))
dedekindicc.lm	⊢ (𝜑 → ∃𝑞 ∈ (𝐴[,]𝐵)𝑞 ∈ 𝐿)
dedekindicc.um	⊢ (𝜑 → ∃𝑟 ∈ (𝐴[,]𝐵)𝑟 ∈ 𝑈)
dedekindicc.lr	⊢ (𝜑 → ∀𝑞 ∈ (𝐴[,]𝐵)(𝑞 ∈ 𝐿 ↔ ∃𝑟 ∈ 𝐿 𝑞 < 𝑟))
dedekindicc.ur	⊢ (𝜑 → ∀𝑟 ∈ (𝐴[,]𝐵)(𝑟 ∈ 𝑈 ↔ ∃𝑞 ∈ 𝑈 𝑞 < 𝑟))
dedekindicc.disj	⊢ (𝜑 → (𝐿 ∩ 𝑈) = ∅)
dedekindicc.loc	⊢ (𝜑 → ∀𝑞 ∈ (𝐴[,]𝐵)∀𝑟 ∈ (𝐴[,]𝐵)(𝑞 < 𝑟 → (𝑞 ∈ 𝐿 ∨ 𝑟 ∈ 𝑈)))

Assertion

Ref	Expression
dedekindicclemub	⊢ (𝜑 → ∃𝑥 ∈ (𝐴[,]𝐵)∀𝑦 ∈ 𝐿 𝑦 < 𝑥)

Distinct variable groups:   𝐴,𝑞,𝑟,𝑦   𝑥,𝐴,𝑦   𝐵,𝑞,𝑟,𝑦   𝑥,𝐵   𝐿,𝑞,𝑦   𝑥,𝐿   𝑈,𝑞,𝑟,𝑦   𝜑,𝑞,𝑦

Allowed substitution hints:   𝜑(𝑥, 𝑟)   𝑈(𝑥)   𝐿(𝑟)

Proof of Theorem dedekindicclemub

Dummy variable 𝑎 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		dedekindicc.um	. . 3 ⊢ (𝜑 → ∃𝑟 ∈ (𝐴[,]𝐵)𝑟 ∈ 𝑈)
2		eleq1w 2299	. . . 4 ⊢ (𝑟 = 𝑎 → (𝑟 ∈ 𝑈 ↔ 𝑎 ∈ 𝑈))
3	2	cbvrexv 2787	. . 3 ⊢ (∃𝑟 ∈ (𝐴[,]𝐵)𝑟 ∈ 𝑈 ↔ ∃𝑎 ∈ (𝐴[,]𝐵)𝑎 ∈ 𝑈)
4	1, 3	sylib 122	. 2 ⊢ (𝜑 → ∃𝑎 ∈ (𝐴[,]𝐵)𝑎 ∈ 𝑈)
5		simprl 535	. . 3 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → 𝑎 ∈ (𝐴[,]𝐵))
6		dedekindicc.a	. . . . 5 ⊢ (𝜑 → 𝐴 ∈ ℝ)
7	6	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → 𝐴 ∈ ℝ)
8		dedekindicc.b	. . . . 5 ⊢ (𝜑 → 𝐵 ∈ ℝ)
9	8	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → 𝐵 ∈ ℝ)
10		dedekindicc.lss	. . . . 5 ⊢ (𝜑 → 𝐿 ⊆ (𝐴[,]𝐵))
11	10	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → 𝐿 ⊆ (𝐴[,]𝐵))
12		dedekindicc.uss	. . . . 5 ⊢ (𝜑 → 𝑈 ⊆ (𝐴[,]𝐵))
13	12	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → 𝑈 ⊆ (𝐴[,]𝐵))
14		dedekindicc.lm	. . . . 5 ⊢ (𝜑 → ∃𝑞 ∈ (𝐴[,]𝐵)𝑞 ∈ 𝐿)
15	14	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → ∃𝑞 ∈ (𝐴[,]𝐵)𝑞 ∈ 𝐿)
16	1	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → ∃𝑟 ∈ (𝐴[,]𝐵)𝑟 ∈ 𝑈)
17		dedekindicc.lr	. . . . 5 ⊢ (𝜑 → ∀𝑞 ∈ (𝐴[,]𝐵)(𝑞 ∈ 𝐿 ↔ ∃𝑟 ∈ 𝐿 𝑞 < 𝑟))
18	17	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → ∀𝑞 ∈ (𝐴[,]𝐵)(𝑞 ∈ 𝐿 ↔ ∃𝑟 ∈ 𝐿 𝑞 < 𝑟))
19		dedekindicc.ur	. . . . 5 ⊢ (𝜑 → ∀𝑟 ∈ (𝐴[,]𝐵)(𝑟 ∈ 𝑈 ↔ ∃𝑞 ∈ 𝑈 𝑞 < 𝑟))
20	19	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → ∀𝑟 ∈ (𝐴[,]𝐵)(𝑟 ∈ 𝑈 ↔ ∃𝑞 ∈ 𝑈 𝑞 < 𝑟))
21		dedekindicc.disj	. . . . 5 ⊢ (𝜑 → (𝐿 ∩ 𝑈) = ∅)
22	21	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → (𝐿 ∩ 𝑈) = ∅)
23		dedekindicc.loc	. . . . 5 ⊢ (𝜑 → ∀𝑞 ∈ (𝐴[,]𝐵)∀𝑟 ∈ (𝐴[,]𝐵)(𝑞 < 𝑟 → (𝑞 ∈ 𝐿 ∨ 𝑟 ∈ 𝑈)))
24	23	adantr 276	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → ∀𝑞 ∈ (𝐴[,]𝐵)∀𝑟 ∈ (𝐴[,]𝐵)(𝑞 < 𝑟 → (𝑞 ∈ 𝐿 ∨ 𝑟 ∈ 𝑈)))
25		simprr 537	. . . 4 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → 𝑎 ∈ 𝑈)
26	7, 9, 11, 13, 15, 16, 18, 20, 22, 24, 25	dedekindicclemuub 15727	. . 3 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → ∀𝑦 ∈ 𝐿 𝑦 < 𝑎)
27		brralrspcev 4189	. . 3 ⊢ ((𝑎 ∈ (𝐴[,]𝐵) ∧ ∀𝑦 ∈ 𝐿 𝑦 < 𝑎) → ∃𝑥 ∈ (𝐴[,]𝐵)∀𝑦 ∈ 𝐿 𝑦 < 𝑥)
28	5, 26, 27	syl2anc 415	. 2 ⊢ ((𝜑 ∧ (𝑎 ∈ (𝐴[,]𝐵) ∧ 𝑎 ∈ 𝑈)) → ∃𝑥 ∈ (𝐴[,]𝐵)∀𝑦 ∈ 𝐿 𝑦 < 𝑥)
29	4, 28	rexlimddv 2673	1 ⊢ (𝜑 → ∃𝑥 ∈ (𝐴[,]𝐵)∀𝑦 ∈ 𝐿 𝑦 < 𝑥)

This proof depends on syntax axioms:   → wi 4   ∧ wa 104   ↔ wb 105   ∨ wo 720   = wceq 1402   ∈ wcel 2209  ∀wral 2528  ∃wrex 2529   ∩ cin 3219   ⊆ wss 3220  ∅c0 3520   class class class wbr 4130  (class class class)co 6085  ℝcr 8178   < clt 8360  [,]cicc 10293

This proof depends on 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 4249  ax-pow 4311  ax-pr 4346  ax-un 4578  ax-setind 4684  ax-cnex 8270  ax-resscn 8271  ax-pre-ltirr 8291  ax-pre-ltwlin 8292  ax-pre-lttrn 8293

This proof depends on definitions:  df-bi 117  df-3or 1010  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-rab 2537  df-v 2823  df-sbc 3052  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-br 4131  df-opab 4193  df-id 4438  df-po 4441  df-iso 4442  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-iota 5337  df-fun 5379  df-fv 5385  df-ov 6088  df-oprab 6089  df-mpo 6090  df-pnf 8362  df-mnf 8363  df-xr 8364  df-ltxr 8365  df-le 8366  df-icc 10297

This theorem is used by: (None)