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Theorem fniniseg2 5535
Description: Inverse point images under functions expressed as abstractions. (Contributed by Stefan O'Rear, 1-Feb-2015.)
Assertion
Ref Expression
fniniseg2  |-  ( F  Fn  A  ->  ( `' F " { B } )  =  {
x  e.  A  | 
( F `  x
)  =  B }
)
Distinct variable groups:    x, A    x, F    x, B

Proof of Theorem fniniseg2
StepHypRef Expression
1 fncnvima2 5534 . 2  |-  ( F  Fn  A  ->  ( `' F " { B } )  =  {
x  e.  A  | 
( F `  x
)  e.  { B } } )
2 funfvex 5431 . . . . 5  |-  ( ( Fun  F  /\  x  e.  dom  F )  -> 
( F `  x
)  e.  _V )
3 elsng 3537 . . . . 5  |-  ( ( F `  x )  e.  _V  ->  (
( F `  x
)  e.  { B } 
<->  ( F `  x
)  =  B ) )
42, 3syl 14 . . . 4  |-  ( ( Fun  F  /\  x  e.  dom  F )  -> 
( ( F `  x )  e.  { B }  <->  ( F `  x )  =  B ) )
54funfni 5218 . . 3  |-  ( ( F  Fn  A  /\  x  e.  A )  ->  ( ( F `  x )  e.  { B }  <->  ( F `  x )  =  B ) )
65rabbidva 2669 . 2  |-  ( F  Fn  A  ->  { x  e.  A  |  ( F `  x )  e.  { B } }  =  { x  e.  A  |  ( F `  x )  =  B } )
71, 6eqtrd 2170 1  |-  ( F  Fn  A  ->  ( `' F " { B } )  =  {
x  e.  A  | 
( F `  x
)  =  B }
)
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 103    <-> wb 104    = wceq 1331    e. wcel 1480   {crab 2418   _Vcvv 2681   {csn 3522   `'ccnv 4533   dom cdm 4534   "cima 4537   Fun wfun 5112    Fn wfn 5113   ` cfv 5118
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 698  ax-5 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-10 1483  ax-11 1484  ax-i12 1485  ax-bndl 1486  ax-4 1487  ax-14 1492  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2119  ax-sep 4041  ax-pow 4093  ax-pr 4126
This theorem depends on definitions:  df-bi 116  df-3an 964  df-tru 1334  df-nf 1437  df-sb 1736  df-eu 2000  df-mo 2001  df-clab 2124  df-cleq 2130  df-clel 2133  df-nfc 2268  df-ral 2419  df-rex 2420  df-rab 2423  df-v 2683  df-sbc 2905  df-un 3070  df-in 3072  df-ss 3079  df-pw 3507  df-sn 3528  df-pr 3529  df-op 3531  df-uni 3732  df-br 3925  df-opab 3985  df-id 4210  df-xp 4540  df-rel 4541  df-cnv 4542  df-co 4543  df-dm 4544  df-rn 4545  df-res 4546  df-ima 4547  df-iota 5083  df-fun 5120  df-fn 5121  df-fv 5126
This theorem is referenced by: (None)
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