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Theorem 0cnALT 8368
Description: Alternate proof of 0cn 8170. (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 8126 . . 3  |-  _i  e.  CC
2 cnegex 8356 . . 3  |-  ( _i  e.  CC  ->  E. x  e.  CC  ( _i  +  x )  =  0 )
31, 2ax-mp 5 . 2  |-  E. x  e.  CC  ( _i  +  x )  =  0
4 addcl 8156 . . . . 5  |-  ( ( _i  e.  CC  /\  x  e.  CC )  ->  ( _i  +  x
)  e.  CC )
51, 4mpan 424 . . . 4  |-  ( x  e.  CC  ->  (
_i  +  x )  e.  CC )
6 eleq1 2294 . . . 4  |-  ( ( _i  +  x )  =  0  ->  (
( _i  +  x
)  e.  CC  <->  0  e.  CC ) )
75, 6syl5ibcom 155 . . 3  |-  ( x  e.  CC  ->  (
( _i  +  x
)  =  0  -> 
0  e.  CC ) )
87rexlimiv 2644 . 2  |-  ( E. x  e.  CC  (
_i  +  x )  =  0  ->  0  e.  CC )
93, 8ax-mp 5 1  |-  0  e.  CC
Colors of variables: wff set class
Syntax hints:    = wceq 1397    e. wcel 2202   E.wrex 2511  (class class class)co 6017   CCcc 8029   0cc0 8031   _ici 8033    + caddc 8034
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 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-ext 2213  ax-resscn 8123  ax-1cn 8124  ax-icn 8126  ax-addcl 8127  ax-addrcl 8128  ax-mulcl 8129  ax-addcom 8131  ax-addass 8133  ax-distr 8135  ax-i2m1 8136  ax-0id 8139  ax-rnegex 8140  ax-cnre 8142
This theorem depends on definitions:  df-bi 117  df-3an 1006  df-tru 1400  df-nf 1509  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-ral 2515  df-rex 2516  df-v 2804  df-un 3204  df-in 3206  df-ss 3213  df-sn 3675  df-pr 3676  df-op 3678  df-uni 3894  df-br 4089  df-iota 5286  df-fv 5334  df-ov 6020
This theorem is referenced by: (None)
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