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Theorem tfrlem7 2955
Description: Lemma for transfinite recursion. The union of all acceptable functions is a function.
Hypotheses
Ref Expression
tfrlem.1 A = {f∣∃x ∈ On (f Fn x ∧ ∀yx (fy) = (G ‘(fy)))}
tfrlem.2 F = A
Assertion
Ref Expression
tfrlem7 Fun F
Distinct variable group(s):   x,y,f,A   x,F,y,f   x,G,y,f

Proof of Theorem tfrlem7
StepHypRef Expression
1 tfrlem.1 . . . 4 A = {f∣∃x ∈ On (f Fn x ∧ ∀yx (fy) = (G ‘(fy)))}
2 tfrlem.2 . . . 4 F = A
31, 2tfrlem6 2954 . . 3 Rel F
42eleq2i 1153 . . . . . . . . 9 (⟨x, u⟩ ∈ F ↔ ⟨x, u⟩ ∈ A)
5 eluni 1922 . . . . . . . . 9 (⟨x, u⟩ ∈ A ↔ ∃g(⟨x, u⟩ ∈ ggA))
64, 5bitr 151 . . . . . . . 8 (⟨x, u⟩ ∈ F ↔ ∃g(⟨x, u⟩ ∈ ggA))
72eleq2i 1153 . . . . . . . . 9 (⟨x, v⟩ ∈ F ↔ ⟨x, v⟩ ∈ A)
8 eluni 1922 . . . . . . . . 9 (⟨x, v⟩ ∈ A ↔ ∃h(⟨x, v⟩ ∈ hhA))
97, 8bitr 151 . . . . . . . 8 (⟨x, v⟩ ∈ F ↔ ∃h(⟨x, v⟩ ∈ hhA))
106, 9anbi12i 369 . . . . . . 7 ((⟨x, u⟩ ∈ F ∧ ⟨x, v⟩ ∈ F) ↔ (∃g(⟨x, u⟩ ∈ ggA) ∧ ∃h(⟨x, v⟩ ∈ hhA)))
11 eeanv 980 . . . . . . 7 (∃gh((⟨x, u⟩ ∈ ggA) ∧ (⟨x, v⟩ ∈ hhA)) ↔ (∃g(⟨x, u⟩ ∈ ggA) ∧ ∃h(⟨x, v⟩ ∈ hhA)))
1210, 11bitr4 154 . . . . . 6 ((⟨x, u⟩ ∈ F ∧ ⟨x, v⟩ ∈ F) ↔ ∃gh((⟨x, u⟩ ∈ ggA) ∧ (⟨x, v⟩ ∈ hhA)))
13 an4 388 . . . . . . . . 9 (((⟨x, u⟩ ∈ ggA) ∧ (⟨x, v⟩ ∈ hhA)) ↔ ((⟨x, u⟩ ∈ g ∧ ⟨x, v⟩ ∈ h) ∧ (gAhA)))
14 ancom 333 . . . . . . . . 9 (((⟨x, u⟩ ∈ g ∧ ⟨x, v⟩ ∈ h) ∧ (gAhA)) ↔ ((gAhA) ∧ (⟨x, u⟩ ∈ g ∧ ⟨x, v⟩ ∈ h)))
1513, 14bitr 151 . . . . . . . 8 (((⟨x, u⟩ ∈ ggA) ∧ (⟨x, v⟩ ∈ hhA)) ↔ ((gAhA) ∧ (⟨x, u⟩ ∈ g ∧ ⟨x, v⟩ ∈ h)))
161, 2tfrlem5 2953 . . . . . . . . 9 ((gAhA) → ((⟨x, u⟩ ∈ g ∧ ⟨x, v⟩ ∈ h) → u = v))
1716imp 277 . . . . . . . 8 (((gAhA) ∧ (⟨x, u⟩ ∈ g ∧ ⟨x, v⟩ ∈ h)) → u = v)
1815, 17sylbi 174 . . . . . . 7 (((⟨x, u⟩ ∈ ggA) ∧ (⟨x, v⟩ ∈ hhA)) → u = v)
191819.23aivv 953 . . . . . 6 (∃gh((⟨x, u⟩ ∈ ggA) ∧ (⟨x, v⟩ ∈ hhA)) → u = v)
2012, 19sylbi 174 . . . . 5 ((⟨x, u⟩ ∈ F ∧ ⟨x, v⟩ ∈ F) → u = v)
2120ax-gen 677 . . . 4 v((⟨x, u⟩ ∈ F ∧ ⟨x, v⟩ ∈ F) → u = v)
2221gen2 681 . . 3 xuv((⟨x, u⟩ ∈ F ∧ ⟨x, v⟩ ∈ F) → u = v)
233, 22pm3.2i 234 . 2 (Rel F ∧ ∀xuv((⟨x, u⟩ ∈ F ∧ ⟨x, v⟩ ∈ F) → u = v))
24 dffun4 2676 . 2 (Fun F ↔ (Rel F ∧ ∀xuv((⟨x, u⟩ ∈ F ∧ ⟨x, v⟩ ∈ F) → u = v)))
2523, 24mpbir 165 1 Fun F
Colors of variables: wff set class
Syntax hints:   → wi 2   ∧ wa 196  ∀wal 672  ∃wex 678   = weq 797  {cab 1090   = wceq 1091   ∈ wcel 1092  ∀wral 1201  ∃wrex 1202  ⟨cop 1810  cuni 1919  Oncon0 2199   ↾ cres 2412  Rel wrel 2415  Fun wfun 2416   Fn wfn 2417   ‘cfv 2422
This theorem is referenced by:  tfrlem9 2957  tfrlem10 2958  tfr1 2962  numthlem 3598  zornlem1 3603  zornlem2 3604  zornlem5 3607  zornlem7 3609
This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6  ax-4 673  ax-5 674  ax-6 675  ax-7 676  ax-gen 677  ax-8 798  ax-9 799  ax-10 800  ax-11 801  ax-12 802  ax-13 804  ax-14 805  ax-16 922  ax-17 925  ax-ext 1074  ax-rep 1075  ax-un 1076  ax-pow 1077
This theorem depends on definitions:  df-bi 128  df-or 197  df-an 198  df-3or 582  df-3an 583  df-ex 679  df-sb 853  df-eu 1009  df-mo 1010  df-clab 1093  df-cleq 1097  df-clel 1099  df-ral 1205  df-rex 1206  df-rab 1208  df-v 1349  df-sbc 1441  df-dif 1489  df-un 1490  df-in 1491  df-ss 1492  df-nul 1708  df-pw 1799  df-sn 1811  df-pr 1812  df-tp 1814  df-op 1815  df-uni 1920  df-tr 2042  df-br 2063  df-opab 2098  df-eprel 2122  df-id 2125  df-po 2128  df-so 2138  df-fr 2169  df-we 2186  df-ord 2202  df-on 2203  df-xp 2424  df-rel 2425  df-cnv 2426  df-co 2427  df-dm 2428  df-rn 2429  df-res 2430  df-ima 2431  df-fun 2432  df-fn 2433  df-fv 2438
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