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Theorem funcnv 2703
Description: The converse of a class is a function iff the class is single-rooted, which means that for any y in the range of A there is at most one x such that xAy. Definition of single-rooted in [Enderton] p. 43. See funcnv2 2702 for a simpler version.
Assertion
Ref Expression
funcnv |- (Fun `'A <-> A.y e. ran AE*x xAy)
Distinct variable group(s):   x,y,A

Proof of Theorem funcnv
StepHypRef Expression
1 visset 1350 . . . . . . 7 |- x e. V
2 visset 1350 . . . . . . 7 |- y e. V
31, 2brelrn 2559 . . . . . 6 |- (xAy -> y e. ran A)
43pm4.71ri 484 . . . . 5 |- (xAy <-> (y e. ran A /\ xAy))
54bimo 1031 . . . 4 |- (E*x xAy <-> E*x(y e. ran A /\ xAy))
6 moanimv 1052 . . . 4 |- (E*x(y e. ran A /\ xAy) <-> (y e. ran A -> E*x xAy))
75, 6bitr 151 . . 3 |- (E*x xAy <-> (y e. ran A -> E*x xAy))
87bial 695 . 2 |- (A.yE*x xAy <-> A.y(y e. ran A -> E*x xAy))
9 funcnv2 2702 . 2 |- (Fun `'A <-> A.yE*x xAy)
10 df-ral 1205 . 2 |- (A.y e. ran AE*x xAy <-> A.y(y e. ran A -> E*x xAy))
118, 9, 103bitr4 158 1 |- (Fun `'A <-> A.y e. ran AE*x xAy)
Colors of variables: wff set class
Syntax hints:   -> wi 2   <-> wb 127   /\ wa 196  A.wal 672  E*wmo 1008   e. wcel 1092  A.wral 1201   class class class wbr 2054  `'ccnv 2409  ran crn 2411  Fun wfun 2416
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-pow 1077
This theorem depends on definitions:  df-bi 128  df-or 197  df-an 198  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-v 1349  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-op 1815  df-br 2063  df-opab 2098  df-id 2125  df-xp 2424  df-rel 2425  df-cnv 2426  df-co 2427  df-dm 2428  df-rn 2429  df-fun 2432
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