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Theorem moani 2256
Description: "At most one" is still true when a conjunct is added. (Contributed by NM, 9-Mar-1995.)
Hypothesis
Ref Expression
moani.1 ∃*xφ
Assertion
Ref Expression
moani ∃*x(ψ φ)

Proof of Theorem moani
StepHypRef Expression
1 moani.1 . 2 ∃*xφ
2 moan 2255 . 2 (∃*xφ∃*x(ψ φ))
31, 2ax-mp 5 1 ∃*x(ψ φ)
Colors of variables: wff setvar class
Syntax hints:   wa 358  ∃*wmo 2205
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925
This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-eu 2208  df-mo 2209
This theorem is referenced by:  euxfr2  3021  ovmpt2x  5712
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