ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  reu5 Unicode version

Theorem reu5 2646
Description: Restricted uniqueness in terms of "at most one." (Contributed by NM, 23-May-1999.) (Revised by NM, 16-Jun-2017.)
Assertion
Ref Expression
reu5  |-  ( E! x  e.  A  ph  <->  ( E. x  e.  A  ph 
/\  E* x  e.  A  ph ) )

Proof of Theorem reu5
StepHypRef Expression
1 eu5 2047 . 2  |-  ( E! x ( x  e.  A  /\  ph )  <->  ( E. x ( x  e.  A  /\  ph )  /\  E* x ( x  e.  A  /\  ph ) ) )
2 df-reu 2424 . 2  |-  ( E! x  e.  A  ph  <->  E! x ( x  e.  A  /\  ph )
)
3 df-rex 2423 . . 3  |-  ( E. x  e.  A  ph  <->  E. x ( x  e.  A  /\  ph )
)
4 df-rmo 2425 . . 3  |-  ( E* x  e.  A  ph  <->  E* x ( x  e.  A  /\  ph )
)
53, 4anbi12i 456 . 2  |-  ( ( E. x  e.  A  ph 
/\  E* x  e.  A  ph )  <->  ( E. x
( x  e.  A  /\  ph )  /\  E* x ( x  e.  A  /\  ph )
) )
61, 2, 53bitr4i 211 1  |-  ( E! x  e.  A  ph  <->  ( E. x  e.  A  ph 
/\  E* x  e.  A  ph ) )
Colors of variables: wff set class
Syntax hints:    /\ wa 103    <-> wb 104   E.wex 1469    e. wcel 1481   E!weu 2000   E*wmo 2001   E.wrex 2418   E!wreu 2419   E*wrmo 2420
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1424  ax-7 1425  ax-gen 1426  ax-ie1 1470  ax-ie2 1471  ax-8 1483  ax-10 1484  ax-11 1485  ax-i12 1486  ax-bndl 1487  ax-4 1488  ax-17 1507  ax-i9 1511  ax-ial 1515  ax-i5r 1516
This theorem depends on definitions:  df-bi 116  df-nf 1438  df-sb 1737  df-eu 2003  df-mo 2004  df-rex 2423  df-reu 2424  df-rmo 2425
This theorem is referenced by:  reurex  2647  reurmo  2648  reu4  2882  reueq  2887  reusv1  4387  fncnv  5197  moriotass  5766  supeuti  6889  infeuti  6924  lteupri  7449  elrealeu  7661  rereceu  7721  exbtwnz  10059  rersqreu  10832  divalglemeunn  11654  divalglemeuneg  11656  bezoutlemeu  11731  pw2dvdseu  11882  dedekindeu  12809  dedekindicclemicc  12818
  Copyright terms: Public domain W3C validator