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Theorem txcnpi 21316
Description: Continuity of a two-argument function at a point. (Contributed by Mario Carneiro, 20-Sep-2015.)
Hypotheses
Ref Expression
txcnpi.1 (𝜑𝐽 ∈ (TopOn‘𝑋))
txcnpi.2 (𝜑𝐾 ∈ (TopOn‘𝑌))
txcnpi.3 (𝜑𝐹 ∈ (((𝐽 ×t 𝐾) CnP 𝐿)‘⟨𝐴, 𝐵⟩))
txcnpi.4 (𝜑𝑈𝐿)
txcnpi.5 (𝜑𝐴𝑋)
txcnpi.6 (𝜑𝐵𝑌)
txcnpi.7 (𝜑 → (𝐴𝐹𝐵) ∈ 𝑈)
Assertion
Ref Expression
txcnpi (𝜑 → ∃𝑢𝐽𝑣𝐾 (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈)))
Distinct variable groups:   𝑣,𝑢,𝐴   𝑢,𝐵,𝑣   𝑢,𝐹,𝑣   𝑢,𝐽,𝑣   𝑢,𝐾,𝑣   𝑢,𝑈,𝑣
Allowed substitution hints:   𝜑(𝑣,𝑢)   𝐿(𝑣,𝑢)   𝑋(𝑣,𝑢)   𝑌(𝑣,𝑢)

Proof of Theorem txcnpi
Dummy variables 𝑤 𝑧 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 txcnpi.3 . . 3 (𝜑𝐹 ∈ (((𝐽 ×t 𝐾) CnP 𝐿)‘⟨𝐴, 𝐵⟩))
2 txcnpi.4 . . 3 (𝜑𝑈𝐿)
3 df-ov 6608 . . . 4 (𝐴𝐹𝐵) = (𝐹‘⟨𝐴, 𝐵⟩)
4 txcnpi.7 . . . 4 (𝜑 → (𝐴𝐹𝐵) ∈ 𝑈)
53, 4syl5eqelr 2709 . . 3 (𝜑 → (𝐹‘⟨𝐴, 𝐵⟩) ∈ 𝑈)
6 cnpimaex 20965 . . 3 ((𝐹 ∈ (((𝐽 ×t 𝐾) CnP 𝐿)‘⟨𝐴, 𝐵⟩) ∧ 𝑈𝐿 ∧ (𝐹‘⟨𝐴, 𝐵⟩) ∈ 𝑈) → ∃𝑤 ∈ (𝐽 ×t 𝐾)(⟨𝐴, 𝐵⟩ ∈ 𝑤 ∧ (𝐹𝑤) ⊆ 𝑈))
71, 2, 5, 6syl3anc 1323 . 2 (𝜑 → ∃𝑤 ∈ (𝐽 ×t 𝐾)(⟨𝐴, 𝐵⟩ ∈ 𝑤 ∧ (𝐹𝑤) ⊆ 𝑈))
8 eqid 2626 . . . . . . . . . 10 (𝐽 ×t 𝐾) = (𝐽 ×t 𝐾)
9 eqid 2626 . . . . . . . . . 10 𝐿 = 𝐿
108, 9cnpf 20956 . . . . . . . . 9 (𝐹 ∈ (((𝐽 ×t 𝐾) CnP 𝐿)‘⟨𝐴, 𝐵⟩) → 𝐹: (𝐽 ×t 𝐾)⟶ 𝐿)
111, 10syl 17 . . . . . . . 8 (𝜑𝐹: (𝐽 ×t 𝐾)⟶ 𝐿)
1211adantr 481 . . . . . . 7 ((𝜑𝑤 ∈ (𝐽 ×t 𝐾)) → 𝐹: (𝐽 ×t 𝐾)⟶ 𝐿)
13 ffun 6007 . . . . . . 7 (𝐹: (𝐽 ×t 𝐾)⟶ 𝐿 → Fun 𝐹)
1412, 13syl 17 . . . . . 6 ((𝜑𝑤 ∈ (𝐽 ×t 𝐾)) → Fun 𝐹)
15 elssuni 4438 . . . . . . 7 (𝑤 ∈ (𝐽 ×t 𝐾) → 𝑤 (𝐽 ×t 𝐾))
16 fdm 6010 . . . . . . . . . 10 (𝐹: (𝐽 ×t 𝐾)⟶ 𝐿 → dom 𝐹 = (𝐽 ×t 𝐾))
1711, 16syl 17 . . . . . . . . 9 (𝜑 → dom 𝐹 = (𝐽 ×t 𝐾))
1817sseq2d 3617 . . . . . . . 8 (𝜑 → (𝑤 ⊆ dom 𝐹𝑤 (𝐽 ×t 𝐾)))
1918biimpar 502 . . . . . . 7 ((𝜑𝑤 (𝐽 ×t 𝐾)) → 𝑤 ⊆ dom 𝐹)
2015, 19sylan2 491 . . . . . 6 ((𝜑𝑤 ∈ (𝐽 ×t 𝐾)) → 𝑤 ⊆ dom 𝐹)
21 funimass3 6290 . . . . . 6 ((Fun 𝐹𝑤 ⊆ dom 𝐹) → ((𝐹𝑤) ⊆ 𝑈𝑤 ⊆ (𝐹𝑈)))
2214, 20, 21syl2anc 692 . . . . 5 ((𝜑𝑤 ∈ (𝐽 ×t 𝐾)) → ((𝐹𝑤) ⊆ 𝑈𝑤 ⊆ (𝐹𝑈)))
2322anbi2d 739 . . . 4 ((𝜑𝑤 ∈ (𝐽 ×t 𝐾)) → ((⟨𝐴, 𝐵⟩ ∈ 𝑤 ∧ (𝐹𝑤) ⊆ 𝑈) ↔ (⟨𝐴, 𝐵⟩ ∈ 𝑤𝑤 ⊆ (𝐹𝑈))))
24 txcnpi.1 . . . . . . 7 (𝜑𝐽 ∈ (TopOn‘𝑋))
25 txcnpi.2 . . . . . . 7 (𝜑𝐾 ∈ (TopOn‘𝑌))
26 eltx 21276 . . . . . . 7 ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) → (𝑤 ∈ (𝐽 ×t 𝐾) ↔ ∀𝑧𝑤𝑢𝐽𝑣𝐾 (𝑧 ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤)))
2724, 25, 26syl2anc 692 . . . . . 6 (𝜑 → (𝑤 ∈ (𝐽 ×t 𝐾) ↔ ∀𝑧𝑤𝑢𝐽𝑣𝐾 (𝑧 ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤)))
2827biimpa 501 . . . . 5 ((𝜑𝑤 ∈ (𝐽 ×t 𝐾)) → ∀𝑧𝑤𝑢𝐽𝑣𝐾 (𝑧 ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤))
29 eleq1 2692 . . . . . . . . . 10 (𝑧 = ⟨𝐴, 𝐵⟩ → (𝑧 ∈ (𝑢 × 𝑣) ↔ ⟨𝐴, 𝐵⟩ ∈ (𝑢 × 𝑣)))
3029anbi1d 740 . . . . . . . . 9 (𝑧 = ⟨𝐴, 𝐵⟩ → ((𝑧 ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) ↔ (⟨𝐴, 𝐵⟩ ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤)))
31302rexbidv 3055 . . . . . . . 8 (𝑧 = ⟨𝐴, 𝐵⟩ → (∃𝑢𝐽𝑣𝐾 (𝑧 ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) ↔ ∃𝑢𝐽𝑣𝐾 (⟨𝐴, 𝐵⟩ ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤)))
3231rspccv 3297 . . . . . . 7 (∀𝑧𝑤𝑢𝐽𝑣𝐾 (𝑧 ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) → (⟨𝐴, 𝐵⟩ ∈ 𝑤 → ∃𝑢𝐽𝑣𝐾 (⟨𝐴, 𝐵⟩ ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤)))
33 sstr2 3595 . . . . . . . . . . . . 13 ((𝑢 × 𝑣) ⊆ 𝑤 → (𝑤 ⊆ (𝐹𝑈) → (𝑢 × 𝑣) ⊆ (𝐹𝑈)))
3433com12 32 . . . . . . . . . . . 12 (𝑤 ⊆ (𝐹𝑈) → ((𝑢 × 𝑣) ⊆ 𝑤 → (𝑢 × 𝑣) ⊆ (𝐹𝑈)))
3534anim2d 588 . . . . . . . . . . 11 (𝑤 ⊆ (𝐹𝑈) → (((𝐴𝑢𝐵𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) → ((𝐴𝑢𝐵𝑣) ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈))))
36 opelxp 5111 . . . . . . . . . . . 12 (⟨𝐴, 𝐵⟩ ∈ (𝑢 × 𝑣) ↔ (𝐴𝑢𝐵𝑣))
3736anbi1i 730 . . . . . . . . . . 11 ((⟨𝐴, 𝐵⟩ ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) ↔ ((𝐴𝑢𝐵𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤))
38 df-3an 1038 . . . . . . . . . . 11 ((𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈)) ↔ ((𝐴𝑢𝐵𝑣) ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈)))
3935, 37, 383imtr4g 285 . . . . . . . . . 10 (𝑤 ⊆ (𝐹𝑈) → ((⟨𝐴, 𝐵⟩ ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) → (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈))))
4039reximdv 3015 . . . . . . . . 9 (𝑤 ⊆ (𝐹𝑈) → (∃𝑣𝐾 (⟨𝐴, 𝐵⟩ ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) → ∃𝑣𝐾 (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈))))
4140reximdv 3015 . . . . . . . 8 (𝑤 ⊆ (𝐹𝑈) → (∃𝑢𝐽𝑣𝐾 (⟨𝐴, 𝐵⟩ ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) → ∃𝑢𝐽𝑣𝐾 (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈))))
4241com12 32 . . . . . . 7 (∃𝑢𝐽𝑣𝐾 (⟨𝐴, 𝐵⟩ ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) → (𝑤 ⊆ (𝐹𝑈) → ∃𝑢𝐽𝑣𝐾 (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈))))
4332, 42syl6 35 . . . . . 6 (∀𝑧𝑤𝑢𝐽𝑣𝐾 (𝑧 ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) → (⟨𝐴, 𝐵⟩ ∈ 𝑤 → (𝑤 ⊆ (𝐹𝑈) → ∃𝑢𝐽𝑣𝐾 (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈)))))
4443impd 447 . . . . 5 (∀𝑧𝑤𝑢𝐽𝑣𝐾 (𝑧 ∈ (𝑢 × 𝑣) ∧ (𝑢 × 𝑣) ⊆ 𝑤) → ((⟨𝐴, 𝐵⟩ ∈ 𝑤𝑤 ⊆ (𝐹𝑈)) → ∃𝑢𝐽𝑣𝐾 (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈))))
4528, 44syl 17 . . . 4 ((𝜑𝑤 ∈ (𝐽 ×t 𝐾)) → ((⟨𝐴, 𝐵⟩ ∈ 𝑤𝑤 ⊆ (𝐹𝑈)) → ∃𝑢𝐽𝑣𝐾 (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈))))
4623, 45sylbid 230 . . 3 ((𝜑𝑤 ∈ (𝐽 ×t 𝐾)) → ((⟨𝐴, 𝐵⟩ ∈ 𝑤 ∧ (𝐹𝑤) ⊆ 𝑈) → ∃𝑢𝐽𝑣𝐾 (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈))))
4746rexlimdva 3029 . 2 (𝜑 → (∃𝑤 ∈ (𝐽 ×t 𝐾)(⟨𝐴, 𝐵⟩ ∈ 𝑤 ∧ (𝐹𝑤) ⊆ 𝑈) → ∃𝑢𝐽𝑣𝐾 (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈))))
487, 47mpd 15 1 (𝜑 → ∃𝑢𝐽𝑣𝐾 (𝐴𝑢𝐵𝑣 ∧ (𝑢 × 𝑣) ⊆ (𝐹𝑈)))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 196  wa 384  w3a 1036   = wceq 1480  wcel 1992  wral 2912  wrex 2913  wss 3560  cop 4159   cuni 4407   × cxp 5077  ccnv 5078  dom cdm 5079  cima 5082  Fun wfun 5844  wf 5846  cfv 5850  (class class class)co 6605  TopOnctopon 20613   CnP ccnp 20934   ×t ctx 21268
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1719  ax-4 1734  ax-5 1841  ax-6 1890  ax-7 1937  ax-8 1994  ax-9 2001  ax-10 2021  ax-11 2036  ax-12 2049  ax-13 2250  ax-ext 2606  ax-sep 4746  ax-nul 4754  ax-pow 4808  ax-pr 4872  ax-un 6903
This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3an 1038  df-tru 1483  df-ex 1702  df-nf 1707  df-sb 1883  df-eu 2478  df-mo 2479  df-clab 2613  df-cleq 2619  df-clel 2622  df-nfc 2756  df-ne 2797  df-ral 2917  df-rex 2918  df-rab 2921  df-v 3193  df-sbc 3423  df-csb 3520  df-dif 3563  df-un 3565  df-in 3567  df-ss 3574  df-nul 3897  df-if 4064  df-pw 4137  df-sn 4154  df-pr 4156  df-op 4160  df-uni 4408  df-iun 4492  df-br 4619  df-opab 4679  df-mpt 4680  df-id 4994  df-xp 5085  df-rel 5086  df-cnv 5087  df-co 5088  df-dm 5089  df-rn 5090  df-res 5091  df-ima 5092  df-iota 5813  df-fun 5852  df-fn 5853  df-f 5854  df-fv 5858  df-ov 6608  df-oprab 6609  df-mpt2 6610  df-1st 7116  df-2nd 7117  df-map 7805  df-topgen 16020  df-top 20616  df-topon 20618  df-cnp 20937  df-tx 21270
This theorem is referenced by:  tmdcn2  21798
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