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Theorem eueq1 2936
Description: Equality has existential uniqueness. (Contributed by NM, 5-Apr-1995.)
Hypothesis
Ref Expression
eueq1.1 𝐴 ∈ V
Assertion
Ref Expression
eueq1 ∃!𝑥 𝑥 = 𝐴
Distinct variable group:   𝑥,𝐴

Proof of Theorem eueq1
StepHypRef Expression
1 eueq1.1 . 2 𝐴 ∈ V
2 eueq 2935 . 2 (𝐴 ∈ V ↔ ∃!𝑥 𝑥 = 𝐴)
31, 2mpbi 145 1 ∃!𝑥 𝑥 = 𝐴
Colors of variables: wff set class
Syntax hints:   = wceq 1364  ∃!weu 2045  wcel 2167  Vcvv 2763
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 710  ax-5 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-ext 2178
This theorem depends on definitions:  df-bi 117  df-nf 1475  df-sb 1777  df-eu 2048  df-mo 2049  df-clab 2183  df-cleq 2189  df-clel 2192  df-v 2765
This theorem is referenced by:  eueq2dc  2937  eueq3dc  2938  fsn  5734
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