ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  0cnALT Unicode version

Theorem 0cnALT 7201
Description: Alternate proof of 0cn 7019. (Contributed by NM, 19-Feb-2005.) (Revised by Mario Carneiro, 27-May-2016.) (Proof modification is discouraged.) (New usage is discouraged.)
Assertion
Ref Expression
0cnALT  |-  0  e.  CC

Proof of Theorem 0cnALT
StepHypRef Expression
1 ax-icn 6979 . . 3  |-  _i  e.  CC
2 cnegex 7189 . . 3  |-  ( _i  e.  CC  ->  E. x  e.  CC  ( _i  +  x )  =  0 )
31, 2ax-mp 7 . 2  |-  E. x  e.  CC  ( _i  +  x )  =  0
4 addcl 7006 . . . . 5  |-  ( ( _i  e.  CC  /\  x  e.  CC )  ->  ( _i  +  x
)  e.  CC )
51, 4mpan 400 . . . 4  |-  ( x  e.  CC  ->  (
_i  +  x )  e.  CC )
6 eleq1 2100 . . . 4  |-  ( ( _i  +  x )  =  0  ->  (
( _i  +  x
)  e.  CC  <->  0  e.  CC ) )
75, 6syl5ibcom 144 . . 3  |-  ( x  e.  CC  ->  (
( _i  +  x
)  =  0  -> 
0  e.  CC ) )
87rexlimiv 2427 . 2  |-  ( E. x  e.  CC  (
_i  +  x )  =  0  ->  0  e.  CC )
93, 8ax-mp 7 1  |-  0  e.  CC
Colors of variables: wff set class
Syntax hints:    = wceq 1243    e. wcel 1393   E.wrex 2307  (class class class)co 5512   CCcc 6887   0cc0 6889   _ici 6891    + caddc 6892
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022  ax-resscn 6976  ax-1cn 6977  ax-icn 6979  ax-addcl 6980  ax-addrcl 6981  ax-mulcl 6982  ax-addcom 6984  ax-addass 6986  ax-distr 6988  ax-i2m1 6989  ax-0id 6992  ax-rnegex 6993  ax-cnre 6995
This theorem depends on definitions:  df-bi 110  df-3an 887  df-tru 1246  df-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-ral 2311  df-rex 2312  df-v 2559  df-un 2922  df-in 2924  df-ss 2931  df-sn 3381  df-pr 3382  df-op 3384  df-uni 3581  df-br 3765  df-iota 4867  df-fv 4910  df-ov 5515
This theorem is referenced by: (None)
  Copyright terms: Public domain W3C validator