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Theorem fniniseg2 5769
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 5768 . 2  |-  ( F  Fn  A  ->  ( `' F " { B } )  =  {
x  e.  A  | 
( F `  x
)  e.  { B } } )
2 funfvex 5656 . . . . 5  |-  ( ( Fun  F  /\  x  e.  dom  F )  -> 
( F `  x
)  e.  _V )
3 elsng 3684 . . . . 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 5432 . . 3  |-  ( ( F  Fn  A  /\  x  e.  A )  ->  ( ( F `  x )  e.  { B }  <->  ( F `  x )  =  B ) )
65rabbidva 2790 . 2  |-  ( F  Fn  A  ->  { x  e.  A  |  ( F `  x )  e.  { B } }  =  { x  e.  A  |  ( F `  x )  =  B } )
71, 6eqtrd 2264 1  |-  ( F  Fn  A  ->  ( `' F " { B } )  =  {
x  e.  A  | 
( F `  x
)  =  B }
)
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    <-> wb 105    = wceq 1397    e. wcel 2202   {crab 2514   _Vcvv 2802   {csn 3669   `'ccnv 4724   dom cdm 4725   "cima 4728   Fun wfun 5320    Fn wfn 5321   ` cfv 5326
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 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-14 2205  ax-ext 2213  ax-sep 4207  ax-pow 4264  ax-pr 4299
This theorem depends on definitions:  df-bi 117  df-3an 1006  df-tru 1400  df-nf 1509  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-ral 2515  df-rex 2516  df-rab 2519  df-v 2804  df-sbc 3032  df-un 3204  df-in 3206  df-ss 3213  df-pw 3654  df-sn 3675  df-pr 3676  df-op 3678  df-uni 3894  df-br 4089  df-opab 4151  df-id 4390  df-xp 4731  df-rel 4732  df-cnv 4733  df-co 4734  df-dm 4735  df-rn 4736  df-res 4737  df-ima 4738  df-iota 5286  df-fun 5328  df-fn 5329  df-fv 5334
This theorem is referenced by: (None)
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