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Theorem hbun 1614
Description: Bound-variable hypothesis builder for the union of classes.
Hypotheses
Ref Expression
hbun.1 |- (y e. A -> A.x y e. A)
hbun.2 |- (y e. B -> A.x y e. B)
Assertion
Ref Expression
hbun |- (y e. (A u. B) -> A.x y e. (A u. B))
Distinct variable group(s):   y,A   y,B   x,y

Proof of Theorem hbun
StepHypRef Expression
1 hbun.1 . . 3 |- (y e. A -> A.x y e. A)
2 hbun.2 . . 3 |- (y e. B -> A.x y e. B)
31, 2hbor 703 . 2 |- ((y e. A \/ y e. B) -> A.x(y e. A \/ y e. B))
4 elun 1601 . 2 |- (y e. (A u. B) <-> (y e. A \/ y e. B))
54bial 695 . 2 |- (A.x y e. (A u. B) <-> A.x(y e. A \/ y e. B))
63, 4, 53imtr4 192 1 |- (y e. (A u. B) -> A.x y e. (A u. B))
Colors of variables: wff set class
Syntax hints:   -> wi 2   \/ wo 195  A.wal 672   e. wcel 1092   u. cun 1485
This theorem is referenced by:  trcl 3489
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-16 922  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  df-un 1490
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