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Theorem suprleubex 8870
Description: The supremum of a nonempty bounded set of reals is less than or equal to an upper bound. (Contributed by NM, 18-Mar-2005.) (Revised by Mario Carneiro, 6-Sep-2014.)
Hypotheses
Ref Expression
suprubex.ex (𝜑 → ∃𝑥 ∈ ℝ (∀𝑦𝐴 ¬ 𝑥 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧𝐴 𝑦 < 𝑧)))
suprubex.ss (𝜑𝐴 ⊆ ℝ)
suprlubex.b (𝜑𝐵 ∈ ℝ)
Assertion
Ref Expression
suprleubex (𝜑 → (sup(𝐴, ℝ, < ) ≤ 𝐵 ↔ ∀𝑧𝐴 𝑧𝐵))
Distinct variable groups:   𝑥,𝐴,𝑦,𝑧   𝜑,𝑥   𝑧,𝐵
Allowed substitution hints:   𝜑(𝑦,𝑧)   𝐵(𝑥,𝑦)

Proof of Theorem suprleubex
Dummy variables 𝑓 𝑔 𝑤 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 lttri3 7999 . . . . . . . 8 ((𝑓 ∈ ℝ ∧ 𝑔 ∈ ℝ) → (𝑓 = 𝑔 ↔ (¬ 𝑓 < 𝑔 ∧ ¬ 𝑔 < 𝑓)))
21adantl 275 . . . . . . 7 ((𝜑 ∧ (𝑓 ∈ ℝ ∧ 𝑔 ∈ ℝ)) → (𝑓 = 𝑔 ↔ (¬ 𝑓 < 𝑔 ∧ ¬ 𝑔 < 𝑓)))
3 suprubex.ex . . . . . . 7 (𝜑 → ∃𝑥 ∈ ℝ (∀𝑦𝐴 ¬ 𝑥 < 𝑦 ∧ ∀𝑦 ∈ ℝ (𝑦 < 𝑥 → ∃𝑧𝐴 𝑦 < 𝑧)))
42, 3supclti 6975 . . . . . 6 (𝜑 → sup(𝐴, ℝ, < ) ∈ ℝ)
5 suprlubex.b . . . . . 6 (𝜑𝐵 ∈ ℝ)
64, 5lenltd 8037 . . . . 5 (𝜑 → (sup(𝐴, ℝ, < ) ≤ 𝐵 ↔ ¬ 𝐵 < sup(𝐴, ℝ, < )))
7 suprubex.ss . . . . . 6 (𝜑𝐴 ⊆ ℝ)
83, 7, 5suprnubex 8869 . . . . 5 (𝜑 → (¬ 𝐵 < sup(𝐴, ℝ, < ) ↔ ∀𝑧𝐴 ¬ 𝐵 < 𝑧))
96, 8bitrd 187 . . . 4 (𝜑 → (sup(𝐴, ℝ, < ) ≤ 𝐵 ↔ ∀𝑧𝐴 ¬ 𝐵 < 𝑧))
10 breq2 3993 . . . . . 6 (𝑤 = 𝑧 → (𝐵 < 𝑤𝐵 < 𝑧))
1110notbid 662 . . . . 5 (𝑤 = 𝑧 → (¬ 𝐵 < 𝑤 ↔ ¬ 𝐵 < 𝑧))
1211cbvralv 2696 . . . 4 (∀𝑤𝐴 ¬ 𝐵 < 𝑤 ↔ ∀𝑧𝐴 ¬ 𝐵 < 𝑧)
139, 12bitr4di 197 . . 3 (𝜑 → (sup(𝐴, ℝ, < ) ≤ 𝐵 ↔ ∀𝑤𝐴 ¬ 𝐵 < 𝑤))
147sselda 3147 . . . . 5 ((𝜑𝑤𝐴) → 𝑤 ∈ ℝ)
155adantr 274 . . . . 5 ((𝜑𝑤𝐴) → 𝐵 ∈ ℝ)
1614, 15lenltd 8037 . . . 4 ((𝜑𝑤𝐴) → (𝑤𝐵 ↔ ¬ 𝐵 < 𝑤))
1716ralbidva 2466 . . 3 (𝜑 → (∀𝑤𝐴 𝑤𝐵 ↔ ∀𝑤𝐴 ¬ 𝐵 < 𝑤))
1813, 17bitr4d 190 . 2 (𝜑 → (sup(𝐴, ℝ, < ) ≤ 𝐵 ↔ ∀𝑤𝐴 𝑤𝐵))
19 breq1 3992 . . 3 (𝑤 = 𝑧 → (𝑤𝐵𝑧𝐵))
2019cbvralv 2696 . 2 (∀𝑤𝐴 𝑤𝐵 ↔ ∀𝑧𝐴 𝑧𝐵)
2118, 20bitrdi 195 1 (𝜑 → (sup(𝐴, ℝ, < ) ≤ 𝐵 ↔ ∀𝑧𝐴 𝑧𝐵))
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wi 4  wa 103  wb 104  wcel 2141  wral 2448  wrex 2449  wss 3121   class class class wbr 3989  supcsup 6959  cr 7773   < clt 7954  cle 7955
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 609  ax-in2 610  ax-io 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528  ax-13 2143  ax-14 2144  ax-ext 2152  ax-sep 4107  ax-pow 4160  ax-pr 4194  ax-un 4418  ax-setind 4521  ax-cnex 7865  ax-resscn 7866  ax-pre-ltirr 7886  ax-pre-ltwlin 7887  ax-pre-lttrn 7888  ax-pre-apti 7889
This theorem depends on definitions:  df-bi 116  df-3an 975  df-tru 1351  df-fal 1354  df-nf 1454  df-sb 1756  df-eu 2022  df-mo 2023  df-clab 2157  df-cleq 2163  df-clel 2166  df-nfc 2301  df-ne 2341  df-nel 2436  df-ral 2453  df-rex 2454  df-reu 2455  df-rmo 2456  df-rab 2457  df-v 2732  df-sbc 2956  df-dif 3123  df-un 3125  df-in 3127  df-ss 3134  df-pw 3568  df-sn 3589  df-pr 3590  df-op 3592  df-uni 3797  df-br 3990  df-opab 4051  df-po 4281  df-iso 4282  df-xp 4617  df-cnv 4619  df-iota 5160  df-riota 5809  df-sup 6961  df-pnf 7956  df-mnf 7957  df-xr 7958  df-ltxr 7959  df-le 7960
This theorem is referenced by:  suprzclex  9310  suplociccex  13397
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