Theorem 0cnALT 8233

Description: Alternate proof of 0cn 8035. (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

Step	Hyp	Ref	Expression
1		ax-icn 7991	. . 3 |- _i e. CC
2		cnegex 8221	. . 3 |- ( _i e. CC -> E. x e. CC ( _i + x ) = 0 )
3	1, 2	ax-mp 5	. 2 |- E. x e. CC ( _i + x ) = 0
4		addcl 8021	. . . . 5 |- ( ( _i e. CC /\ x e. CC ) -> ( _i + x ) e. CC )
5	1, 4	mpan 424	. . . 4 |- ( x e. CC -> ( _i + x ) e. CC )
6		eleq1 2259	. . . 4 |- ( ( _i + x ) = 0 -> ( ( _i + x ) e. CC <-> 0 e. CC ) )
7	5, 6	syl5ibcom 155	. . 3 |- ( x e. CC -> ( ( _i + x ) = 0 -> 0 e. CC ) )
8	7	rexlimiv 2608	. 2 |- ( E. x e. CC ( _i + x ) = 0 -> 0 e. CC )
9	3, 8	ax-mp 5	1 |- 0 e. CC

Syntax hints:   = wceq 1364   e. wcel 2167   E.wrex 2476  (class class class)co 5925   CCcc 7894   0cc0 7896   _ici 7898   + caddc 7899

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 710  ax-5 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-ext 2178  ax-resscn 7988  ax-1cn 7989  ax-icn 7991  ax-addcl 7992  ax-addrcl 7993  ax-mulcl 7994  ax-addcom 7996  ax-addass 7998  ax-distr 8000  ax-i2m1 8001  ax-0id 8004  ax-rnegex 8005  ax-cnre 8007

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-nf 1475  df-sb 1777  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-ral 2480  df-rex 2481  df-v 2765  df-un 3161  df-in 3163  df-ss 3170  df-sn 3629  df-pr 3630  df-op 3632  df-uni 3841  df-br 4035  df-iota 5220  df-fv 5267  df-ov 5928

This theorem is referenced by: (None)