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Theorem bj-prexg 37183
Description: Existence of unordered pairs formed on sets, proved from ax-bj-sn 37177 and ax-bj-bun 37181. Contrary to bj-prex 37184, this proof is intuitionistically valid and does not require ax-nul 5249. (Contributed by BJ, 12-Jan-2025.) (Proof modification is discouraged.)
Assertion
Ref Expression
bj-prexg ((𝐴𝑉𝐵𝑊) → {𝐴, 𝐵} ∈ V)

Proof of Theorem bj-prexg
StepHypRef Expression
1 df-pr 4581 . 2 {𝐴, 𝐵} = ({𝐴} ∪ {𝐵})
2 bj-snexg 37178 . . 3 (𝐴𝑉 → {𝐴} ∈ V)
3 bj-snexg 37178 . . 3 (𝐵𝑊 → {𝐵} ∈ V)
4 bj-unexg 37182 . . 3 (({𝐴} ∈ V ∧ {𝐵} ∈ V) → ({𝐴} ∪ {𝐵}) ∈ V)
52, 3, 4syl2an 596 . 2 ((𝐴𝑉𝐵𝑊) → ({𝐴} ∪ {𝐵}) ∈ V)
61, 5eqeltrid 2838 1 ((𝐴𝑉𝐵𝑊) → {𝐴, 𝐵} ∈ V)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 395  wcel 2113  Vcvv 3438  cun 3897  {csn 4578  {cpr 4580
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1968  ax-7 2009  ax-8 2115  ax-9 2123  ax-12 2182  ax-ext 2706  ax-bj-sn 37177  ax-bj-bun 37181
This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-tru 1544  df-ex 1781  df-sb 2068  df-clab 2713  df-cleq 2726  df-clel 2809  df-v 3440  df-un 3904  df-sn 4579  df-pr 4581
This theorem is referenced by: (None)
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