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Theorem brcodir 5012
Description: Two ways of saying that two elements have an upper bound. (Contributed by Mario Carneiro, 3-Nov-2015.)
Assertion
Ref Expression
brcodir ((𝐴𝑉𝐵𝑊) → (𝐴(𝑅𝑅)𝐵 ↔ ∃𝑧(𝐴𝑅𝑧𝐵𝑅𝑧)))
Distinct variable groups:   𝑧,𝐴   𝑧,𝐵   𝑧,𝑅   𝑧,𝑉   𝑧,𝑊

Proof of Theorem brcodir
StepHypRef Expression
1 brcog 4790 . 2 ((𝐴𝑉𝐵𝑊) → (𝐴(𝑅𝑅)𝐵 ↔ ∃𝑧(𝐴𝑅𝑧𝑧𝑅𝐵)))
2 vex 2740 . . . . . 6 𝑧 ∈ V
3 brcnvg 4804 . . . . . 6 ((𝑧 ∈ V ∧ 𝐵𝑊) → (𝑧𝑅𝐵𝐵𝑅𝑧))
42, 3mpan 424 . . . . 5 (𝐵𝑊 → (𝑧𝑅𝐵𝐵𝑅𝑧))
54anbi2d 464 . . . 4 (𝐵𝑊 → ((𝐴𝑅𝑧𝑧𝑅𝐵) ↔ (𝐴𝑅𝑧𝐵𝑅𝑧)))
65adantl 277 . . 3 ((𝐴𝑉𝐵𝑊) → ((𝐴𝑅𝑧𝑧𝑅𝐵) ↔ (𝐴𝑅𝑧𝐵𝑅𝑧)))
76exbidv 1825 . 2 ((𝐴𝑉𝐵𝑊) → (∃𝑧(𝐴𝑅𝑧𝑧𝑅𝐵) ↔ ∃𝑧(𝐴𝑅𝑧𝐵𝑅𝑧)))
81, 7bitrd 188 1 ((𝐴𝑉𝐵𝑊) → (𝐴(𝑅𝑅)𝐵 ↔ ∃𝑧(𝐴𝑅𝑧𝐵𝑅𝑧)))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 104  wb 105  wex 1492  wcel 2148  Vcvv 2737   class class class wbr 4000  ccnv 4622  ccom 4627
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-14 2151  ax-ext 2159  ax-sep 4118  ax-pow 4171  ax-pr 4206
This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1461  df-sb 1763  df-eu 2029  df-mo 2030  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-v 2739  df-un 3133  df-in 3135  df-ss 3142  df-pw 3576  df-sn 3597  df-pr 3598  df-op 3600  df-br 4001  df-opab 4062  df-cnv 4631  df-co 4632
This theorem is referenced by:  codir  5013
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