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Theorem axdc 8899
Description: This theorem derives ax-dc 8824 using ax-ac 8837 and ax-inf 8053. Thus, AC implies DC, but not vice-versa (so that ZFC is strictly stronger than ZF+DC). (New usage is discouraged.) (Contributed by Mario Carneiro, 25-Jan-2013.)
Assertion
Ref Expression
axdc  |-  ( ( E. y E. z 
y x z  /\  ran  x  C_  dom  x )  ->  E. f A. n  e.  om  ( f `  n ) x ( f `  suc  n
) )
Distinct variable group:    f, n, x, y, z

Proof of Theorem axdc
Dummy variables  v 
g  u  w are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 breq2 4437 . . . . . . . . 9  |-  ( w  =  z  ->  (
u x w  <->  u x
z ) )
21cbvabv 2584 . . . . . . . 8  |-  { w  |  u x w }  =  { z  |  u x z }
3 breq1 4436 . . . . . . . . 9  |-  ( u  =  v  ->  (
u x z  <->  v x
z ) )
43abbidv 2577 . . . . . . . 8  |-  ( u  =  v  ->  { z  |  u x z }  =  { z  |  v x z } )
52, 4syl5eq 2494 . . . . . . 7  |-  ( u  =  v  ->  { w  |  u x w }  =  { z  |  v x z } )
65fveq2d 5856 . . . . . 6  |-  ( u  =  v  ->  (
g `  { w  |  u x w }
)  =  ( g `
 { z  |  v x z } ) )
76cbvmptv 4524 . . . . 5  |-  ( u  e.  _V  |->  ( g `
 { w  |  u x w }
) )  =  ( v  e.  _V  |->  ( g `  { z  |  v x z } ) )
8 rdgeq1 7075 . . . . 5  |-  ( ( u  e.  _V  |->  ( g `  { w  |  u x w }
) )  =  ( v  e.  _V  |->  ( g `  { z  |  v x z } ) )  ->  rec ( ( u  e. 
_V  |->  ( g `  { w  |  u x w } ) ) ,  y )  =  rec ( ( v  e.  _V  |->  ( g `  { z  |  v x z } ) ) ,  y ) )
9 reseq1 5253 . . . . 5  |-  ( rec ( ( u  e. 
_V  |->  ( g `  { w  |  u x w } ) ) ,  y )  =  rec ( ( v  e.  _V  |->  ( g `  { z  |  v x z } ) ) ,  y )  ->  ( rec ( ( u  e. 
_V  |->  ( g `  { w  |  u x w } ) ) ,  y )  |`  om )  =  ( rec ( ( v  e.  _V  |->  ( g `
 { z  |  v x z } ) ) ,  y )  |`  om )
)
107, 8, 9mp2b 10 . . . 4  |-  ( rec ( ( u  e. 
_V  |->  ( g `  { w  |  u x w } ) ) ,  y )  |`  om )  =  ( rec ( ( v  e.  _V  |->  ( g `
 { z  |  v x z } ) ) ,  y )  |`  om )
1110axdclem2 8898 . . 3  |-  ( E. z  y x z  ->  ( ran  x  C_ 
dom  x  ->  E. f A. n  e.  om  ( f `  n
) x ( f `
 suc  n )
) )
1211exlimiv 1707 . 2  |-  ( E. y E. z  y x z  ->  ( ran  x  C_  dom  x  ->  E. f A. n  e. 
om  ( f `  n ) x ( f `  suc  n
) ) )
1312imp 429 1  |-  ( ( E. y E. z 
y x z  /\  ran  x  C_  dom  x )  ->  E. f A. n  e.  om  ( f `  n ) x ( f `  suc  n
) )
Colors of variables: wff setvar class
Syntax hints:    -> wi 4    /\ wa 369    = wceq 1381   E.wex 1597   {cab 2426   A.wral 2791   _Vcvv 3093    C_ wss 3458   class class class wbr 4433    |-> cmpt 4491   suc csuc 4866   dom cdm 4985   ran crn 4986    |` cres 4987   ` cfv 5574   omcom 6681   reccrdg 7073
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1603  ax-4 1616  ax-5 1689  ax-6 1732  ax-7 1774  ax-8 1804  ax-9 1806  ax-10 1821  ax-11 1826  ax-12 1838  ax-13 1983  ax-ext 2419  ax-rep 4544  ax-sep 4554  ax-nul 4562  ax-pow 4611  ax-pr 4672  ax-un 6573  ax-inf2 8056  ax-ac2 8841
This theorem depends on definitions:  df-bi 185  df-or 370  df-an 371  df-3or 973  df-3an 974  df-tru 1384  df-ex 1598  df-nf 1602  df-sb 1725  df-eu 2270  df-mo 2271  df-clab 2427  df-cleq 2433  df-clel 2436  df-nfc 2591  df-ne 2638  df-ral 2796  df-rex 2797  df-reu 2798  df-rab 2800  df-v 3095  df-sbc 3312  df-csb 3418  df-dif 3461  df-un 3463  df-in 3465  df-ss 3472  df-pss 3474  df-nul 3768  df-if 3923  df-pw 3995  df-sn 4011  df-pr 4013  df-tp 4015  df-op 4017  df-uni 4231  df-iun 4313  df-br 4434  df-opab 4492  df-mpt 4493  df-tr 4527  df-eprel 4777  df-id 4781  df-po 4786  df-so 4787  df-fr 4824  df-we 4826  df-ord 4867  df-on 4868  df-lim 4869  df-suc 4870  df-xp 4991  df-rel 4992  df-cnv 4993  df-co 4994  df-dm 4995  df-rn 4996  df-res 4997  df-ima 4998  df-iota 5537  df-fun 5576  df-fn 5577  df-f 5578  df-f1 5579  df-fo 5580  df-f1o 5581  df-fv 5582  df-om 6682  df-recs 7040  df-rdg 7074  df-ac 8495
This theorem is referenced by: (None)
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