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Theorem elrnrexdmb 5698
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 5284 . . 3  |-  ( Fun 
F  <->  F  Fn  dom  F )
2 fvelrnb 5604 . . 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 2195 . . 3  |-  ( Y  =  ( F `  x )  <->  ( F `  x )  =  Y )
54rexbii 2501 . 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 1364    e. wcel 2164   E.wrex 2473   dom cdm 4659   ran crn 4660   Fun wfun 5248    Fn wfn 5249   ` cfv 5254
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 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-14 2167  ax-ext 2175  ax-sep 4147  ax-pow 4203  ax-pr 4238
This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-nf 1472  df-sb 1774  df-eu 2045  df-mo 2046  df-clab 2180  df-cleq 2186  df-clel 2189  df-nfc 2325  df-ral 2477  df-rex 2478  df-v 2762  df-sbc 2986  df-un 3157  df-in 3159  df-ss 3166  df-pw 3603  df-sn 3624  df-pr 3625  df-op 3627  df-uni 3836  df-br 4030  df-opab 4091  df-mpt 4092  df-id 4324  df-xp 4665  df-rel 4666  df-cnv 4667  df-co 4668  df-dm 4669  df-rn 4670  df-iota 5215  df-fun 5256  df-fn 5257  df-fv 5262
This theorem is referenced by: (None)
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