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Theorem cnfnc 28173
 Description: Basic continuity property of a continuous functional. (Contributed by NM, 11-Feb-2006.) (Revised by Mario Carneiro, 16-Nov-2013.) (New usage is discouraged.)
Assertion
Ref Expression
cnfnc ((𝑇 ∈ ConFn ∧ 𝐴 ∈ ℋ ∧ 𝐵 ∈ ℝ+) → ∃𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝐴)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝐵))
Distinct variable groups:   𝑥,𝑦,𝐴   𝑥,𝐵,𝑦   𝑥,𝑇,𝑦

Proof of Theorem cnfnc
Dummy variables 𝑤 𝑧 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 elcnfn 28125 . . . 4 (𝑇 ∈ ConFn ↔ (𝑇: ℋ⟶ℂ ∧ ∀𝑧 ∈ ℋ ∀𝑤 ∈ ℝ+𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝑧)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝑧))) < 𝑤)))
21simprbi 479 . . 3 (𝑇 ∈ ConFn → ∀𝑧 ∈ ℋ ∀𝑤 ∈ ℝ+𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝑧)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝑧))) < 𝑤))
3 oveq2 6557 . . . . . . . 8 (𝑧 = 𝐴 → (𝑦 𝑧) = (𝑦 𝐴))
43fveq2d 6107 . . . . . . 7 (𝑧 = 𝐴 → (norm‘(𝑦 𝑧)) = (norm‘(𝑦 𝐴)))
54breq1d 4593 . . . . . 6 (𝑧 = 𝐴 → ((norm‘(𝑦 𝑧)) < 𝑥 ↔ (norm‘(𝑦 𝐴)) < 𝑥))
6 fveq2 6103 . . . . . . . . 9 (𝑧 = 𝐴 → (𝑇𝑧) = (𝑇𝐴))
76oveq2d 6565 . . . . . . . 8 (𝑧 = 𝐴 → ((𝑇𝑦) − (𝑇𝑧)) = ((𝑇𝑦) − (𝑇𝐴)))
87fveq2d 6107 . . . . . . 7 (𝑧 = 𝐴 → (abs‘((𝑇𝑦) − (𝑇𝑧))) = (abs‘((𝑇𝑦) − (𝑇𝐴))))
98breq1d 4593 . . . . . 6 (𝑧 = 𝐴 → ((abs‘((𝑇𝑦) − (𝑇𝑧))) < 𝑤 ↔ (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝑤))
105, 9imbi12d 333 . . . . 5 (𝑧 = 𝐴 → (((norm‘(𝑦 𝑧)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝑧))) < 𝑤) ↔ ((norm‘(𝑦 𝐴)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝑤)))
1110rexralbidv 3040 . . . 4 (𝑧 = 𝐴 → (∃𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝑧)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝑧))) < 𝑤) ↔ ∃𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝐴)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝑤)))
12 breq2 4587 . . . . . 6 (𝑤 = 𝐵 → ((abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝑤 ↔ (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝐵))
1312imbi2d 329 . . . . 5 (𝑤 = 𝐵 → (((norm‘(𝑦 𝐴)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝑤) ↔ ((norm‘(𝑦 𝐴)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝐵)))
1413rexralbidv 3040 . . . 4 (𝑤 = 𝐵 → (∃𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝐴)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝑤) ↔ ∃𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝐴)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝐵)))
1511, 14rspc2v 3293 . . 3 ((𝐴 ∈ ℋ ∧ 𝐵 ∈ ℝ+) → (∀𝑧 ∈ ℋ ∀𝑤 ∈ ℝ+𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝑧)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝑧))) < 𝑤) → ∃𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝐴)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝐵)))
162, 15syl5com 31 . 2 (𝑇 ∈ ConFn → ((𝐴 ∈ ℋ ∧ 𝐵 ∈ ℝ+) → ∃𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝐴)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝐵)))
17163impib 1254 1 ((𝑇 ∈ ConFn ∧ 𝐴 ∈ ℋ ∧ 𝐵 ∈ ℝ+) → ∃𝑥 ∈ ℝ+𝑦 ∈ ℋ ((norm‘(𝑦 𝐴)) < 𝑥 → (abs‘((𝑇𝑦) − (𝑇𝐴))) < 𝐵))
 Colors of variables: wff setvar class Syntax hints:   → wi 4   ∧ wa 383   ∧ w3a 1031   = wceq 1475   ∈ wcel 1977  ∀wral 2896  ∃wrex 2897   class class class wbr 4583  ⟶wf 5800  ‘cfv 5804  (class class class)co 6549  ℂcc 9813   < clt 9953   − cmin 10145  ℝ+crp 11708  abscabs 13822   ℋchil 27160  normℎcno 27164   −ℎ cmv 27166  ConFnccnfn 27194 This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-8 1979  ax-9 1986  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590  ax-sep 4709  ax-nul 4717  ax-pow 4769  ax-pr 4833  ax-un 6847  ax-cnex 9871  ax-hilex 27240 This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3an 1033  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-eu 2462  df-mo 2463  df-clab 2597  df-cleq 2603  df-clel 2606  df-nfc 2740  df-ral 2901  df-rex 2902  df-rab 2905  df-v 3175  df-sbc 3403  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-op 4132  df-uni 4373  df-br 4584  df-opab 4644  df-id 4953  df-xp 5044  df-rel 5045  df-cnv 5046  df-co 5047  df-dm 5048  df-rn 5049  df-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-fv 5812  df-ov 6552  df-oprab 6553  df-mpt2 6554  df-map 7746  df-cnfn 28090 This theorem is referenced by:  nmcfnexi  28294
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