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Theorem vtocl2 1379
Description: Implicit substitution of classes for set variables.
Hypotheses
Ref Expression
vtocl2.1 |- A e. V
vtocl2.2 |- B e. V
vtocl2.3 |- ((x = A /\ y = B) -> (ph <-> ps))
vtocl2.4 |- ph
Assertion
Ref Expression
vtocl2 |- ps
Distinct variable group(s):   x,y,A   x,B,y   ps,x,y

Proof of Theorem vtocl2
StepHypRef Expression
1 vtocl2.1 . . . . 5 |- A e. V
21isseti 1352 . . . 4 |- E.x x = A
3 vtocl2.2 . . . . 5 |- B e. V
43isseti 1352 . . . 4 |- E.y y = B
5 eeanv 980 . . . . 5 |- (E.xE.y(x = A /\ y = B) <-> (E.x x = A /\ E.y y = B))
6 vtocl2.3 . . . . . . . 8 |- ((x = A /\ y = B) -> (ph <-> ps))
76biimpd 135 . . . . . . 7 |- ((x = A /\ y = B) -> (ph -> ps))
8719.22i 723 . . . . . 6 |- (E.y(x = A /\ y = B) -> E.y(ph -> ps))
9819.22i 723 . . . . 5 |- (E.xE.y(x = A /\ y = B) -> E.xE.y(ph -> ps))
105, 9sylbir 176 . . . 4 |- ((E.x x = A /\ E.y y = B) -> E.xE.y(ph -> ps))
112, 4, 10mp2an 520 . . 3 |- E.xE.y(ph -> ps)
12 19.36v 958 . . . . 5 |- (E.y(ph -> ps) <-> (A.yph -> ps))
1312biex 733 . . . 4 |- (E.xE.y(ph -> ps) <-> E.x(A.yph -> ps))
14 19.36v 958 . . . 4 |- (E.x(A.yph -> ps) <-> (A.xA.yph -> ps))
1513, 14bitr 151 . . 3 |- (E.xE.y(ph -> ps) <-> (A.xA.yph -> ps))
1611, 15mpbi 164 . 2 |- (A.xA.yph -> ps)
17 vtocl2.4 . . 3 |- ph
1817ax-gen 677 . 2 |- A.yph
1916, 18mpg 684 1 |- ps
Colors of variables: wff set class
Syntax hints:   -> wi 2   <-> wb 127   /\ wa 196  A.wal 672  E.wex 678   = wceq 1091   e. wcel 1092  Vcvv 1348
This theorem is referenced by:  caoprcom 3067  caoprord 3070  ersym 3209
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-9 799  ax-12 802  ax-17 925  ax-ext 1074
This theorem depends on definitions:  df-bi 128  df-or 197  df-an 198  df-ex 679  df-sb 853  df-clab 1093  df-cleq 1097  df-clel 1099  df-v 1349
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