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Theorem elrnrexdmb 5795
Description: For any element in the range of a function there is an element in the domain of the function for which the function value is the element of the range. (Contributed by Alexander van der Vekens, 17-Dec-2017.)
Assertion
Ref Expression
elrnrexdmb  |-  ( Fun 
F  ->  ( Y  e.  ran  F  <->  E. x  e.  dom  F  Y  =  ( F `  x
) ) )
Distinct variable groups:    x, F    x, Y

Proof of Theorem elrnrexdmb
StepHypRef Expression
1 funfn 5363 . . 3  |-  ( Fun 
F  <->  F  Fn  dom  F )
2 fvelrnb 5702 . . 3  |-  ( F  Fn  dom  F  -> 
( Y  e.  ran  F  <->  E. x  e.  dom  F ( F `  x
)  =  Y ) )
31, 2sylbi 121 . 2  |-  ( Fun 
F  ->  ( Y  e.  ran  F  <->  E. x  e.  dom  F ( F `
 x )  =  Y ) )
4 eqcom 2233 . . 3  |-  ( Y  =  ( F `  x )  <->  ( F `  x )  =  Y )
54rexbii 2540 . 2  |-  ( E. x  e.  dom  F  Y  =  ( F `  x )  <->  E. x  e.  dom  F ( F `
 x )  =  Y )
63, 5bitr4di 198 1  |-  ( Fun 
F  ->  ( Y  e.  ran  F  <->  E. x  e.  dom  F  Y  =  ( F `  x
) ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 105    = wceq 1398    e. wcel 2202   E.wrex 2512   dom cdm 4731   ran crn 4732   Fun wfun 5327    Fn wfn 5328   ` cfv 5333
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 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-14 2205  ax-ext 2213  ax-sep 4212  ax-pow 4270  ax-pr 4305
This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2364  df-ral 2516  df-rex 2517  df-v 2805  df-sbc 3033  df-un 3205  df-in 3207  df-ss 3214  df-pw 3658  df-sn 3679  df-pr 3680  df-op 3682  df-uni 3899  df-br 4094  df-opab 4156  df-mpt 4157  df-id 4396  df-xp 4737  df-rel 4738  df-cnv 4739  df-co 4740  df-dm 4741  df-rn 4742  df-iota 5293  df-fun 5335  df-fn 5336  df-fv 5341
This theorem is referenced by:  edgiedgbg  15989  uhgrspansubgrlem  16200
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