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Theorem tridceq 16858
Description: Real trichotomy implies decidability of real number equality. Or in other words, analytic LPO implies analytic WLPO (see trilpo 16844 and redcwlpo 16857). Thus, this is an analytic analogue to lpowlpo 7461. (Contributed by Jim Kingdon, 24-Jul-2024.)
Assertion
Ref Expression
tridceq  |-  ( A. x  e.  RR  A. y  e.  RR  ( x  < 
y  \/  x  =  y  \/  y  < 
x )  ->  A. x  e.  RR  A. y  e.  RR DECID  x  =  y )
Distinct variable group:    x, y

Proof of Theorem tridceq
StepHypRef Expression
1 ltne 8360 . . . . . . 7  |-  ( ( x  e.  RR  /\  x  <  y )  -> 
y  =/=  x )
21ex 115 . . . . . 6  |-  ( x  e.  RR  ->  (
x  <  y  ->  y  =/=  x ) )
32adantr 276 . . . . 5  |-  ( ( x  e.  RR  /\  y  e.  RR )  ->  ( x  <  y  ->  y  =/=  x ) )
4 olc 719 . . . . . 6  |-  ( x  =/=  y  ->  (
x  =  y  \/  x  =/=  y ) )
5 necom 2498 . . . . . 6  |-  ( y  =/=  x  <->  x  =/=  y )
6 dcne 2425 . . . . . 6  |-  (DECID  x  =  y  <->  ( x  =  y  \/  x  =/=  y ) )
74, 5, 63imtr4i 201 . . . . 5  |-  ( y  =/=  x  -> DECID  x  =  y
)
83, 7syl6 33 . . . 4  |-  ( ( x  e.  RR  /\  y  e.  RR )  ->  ( x  <  y  -> DECID  x  =  y ) )
9 orc 720 . . . . . 6  |-  ( x  =  y  ->  (
x  =  y  \/  x  =/=  y ) )
109, 6sylibr 134 . . . . 5  |-  ( x  =  y  -> DECID  x  =  y
)
1110a1i 9 . . . 4  |-  ( ( x  e.  RR  /\  y  e.  RR )  ->  ( x  =  y  -> DECID 
x  =  y ) )
12 ltne 8360 . . . . . . 7  |-  ( ( y  e.  RR  /\  y  <  x )  ->  x  =/=  y )
1312ex 115 . . . . . 6  |-  ( y  e.  RR  ->  (
y  <  x  ->  x  =/=  y ) )
1413adantl 277 . . . . 5  |-  ( ( x  e.  RR  /\  y  e.  RR )  ->  ( y  <  x  ->  x  =/=  y ) )
154, 6sylibr 134 . . . . 5  |-  ( x  =/=  y  -> DECID  x  =  y
)
1614, 15syl6 33 . . . 4  |-  ( ( x  e.  RR  /\  y  e.  RR )  ->  ( y  <  x  -> DECID  x  =  y ) )
178, 11, 163jaod 1341 . . 3  |-  ( ( x  e.  RR  /\  y  e.  RR )  ->  ( ( x  < 
y  \/  x  =  y  \/  y  < 
x )  -> DECID  x  =  y
) )
1817ralimdva 2611 . 2  |-  ( x  e.  RR  ->  ( A. y  e.  RR  ( x  <  y  \/  x  =  y  \/  y  <  x )  ->  A. y  e.  RR DECID  x  =  y ) )
1918ralimia 2605 1  |-  ( A. x  e.  RR  A. y  e.  RR  ( x  < 
y  \/  x  =  y  \/  y  < 
x )  ->  A. x  e.  RR  A. y  e.  RR DECID  x  =  y )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    \/ wo 716  DECID wdc 842    \/ w3o 1004    e. wcel 2205    =/= wne 2414   A.wral 2522   class class class wbr 4111   RRcr 8128    < clt 8310
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-in1 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2207  ax-14 2208  ax-ext 2216  ax-sep 4230  ax-pow 4289  ax-pr 4324  ax-un 4556  ax-setind 4661  ax-cnex 8220  ax-resscn 8221  ax-pre-ltirr 8241
This theorem depends on definitions:  df-bi 117  df-dc 843  df-3or 1006  df-3an 1007  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1812  df-eu 2085  df-mo 2086  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-ne 2415  df-nel 2510  df-ral 2527  df-rex 2528  df-rab 2531  df-v 2817  df-dif 3215  df-un 3217  df-in 3219  df-ss 3226  df-pw 3673  df-sn 3697  df-pr 3698  df-op 3700  df-uni 3917  df-br 4112  df-opab 4174  df-xp 4757  df-pnf 8312  df-mnf 8313  df-ltxr 8315
This theorem is referenced by:  dcapnconstALT  16865
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