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Theorem ffnfv 5546
Description: A function maps to a class to which all values belong. (Contributed by NM, 3-Dec-2003.)
Assertion
Ref Expression
ffnfv  |-  ( F : A --> B  <->  ( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B
) )
Distinct variable groups:    x, A    x, B    x, F

Proof of Theorem ffnfv
Dummy variable  y is distinct from all other variables.
StepHypRef Expression
1 ffn 5242 . . 3  |-  ( F : A --> B  ->  F  Fn  A )
2 ffvelrn 5521 . . . 4  |-  ( ( F : A --> B  /\  x  e.  A )  ->  ( F `  x
)  e.  B )
32ralrimiva 2482 . . 3  |-  ( F : A --> B  ->  A. x  e.  A  ( F `  x )  e.  B )
41, 3jca 304 . 2  |-  ( F : A --> B  -> 
( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B ) )
5 simpl 108 . . 3  |-  ( ( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B )  ->  F  Fn  A )
6 fvelrnb 5437 . . . . . 6  |-  ( F  Fn  A  ->  (
y  e.  ran  F  <->  E. x  e.  A  ( F `  x )  =  y ) )
76biimpd 143 . . . . 5  |-  ( F  Fn  A  ->  (
y  e.  ran  F  ->  E. x  e.  A  ( F `  x )  =  y ) )
8 nfra1 2443 . . . . . 6  |-  F/ x A. x  e.  A  ( F `  x )  e.  B
9 nfv 1493 . . . . . 6  |-  F/ x  y  e.  B
10 rsp 2457 . . . . . . 7  |-  ( A. x  e.  A  ( F `  x )  e.  B  ->  ( x  e.  A  ->  ( F `  x )  e.  B ) )
11 eleq1 2180 . . . . . . . 8  |-  ( ( F `  x )  =  y  ->  (
( F `  x
)  e.  B  <->  y  e.  B ) )
1211biimpcd 158 . . . . . . 7  |-  ( ( F `  x )  e.  B  ->  (
( F `  x
)  =  y  -> 
y  e.  B ) )
1310, 12syl6 33 . . . . . 6  |-  ( A. x  e.  A  ( F `  x )  e.  B  ->  ( x  e.  A  ->  (
( F `  x
)  =  y  -> 
y  e.  B ) ) )
148, 9, 13rexlimd 2523 . . . . 5  |-  ( A. x  e.  A  ( F `  x )  e.  B  ->  ( E. x  e.  A  ( F `  x )  =  y  ->  y  e.  B ) )
157, 14sylan9 406 . . . 4  |-  ( ( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B )  -> 
( y  e.  ran  F  ->  y  e.  B
) )
1615ssrdv 3073 . . 3  |-  ( ( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B )  ->  ran  F  C_  B )
17 df-f 5097 . . 3  |-  ( F : A --> B  <->  ( F  Fn  A  /\  ran  F  C_  B ) )
185, 16, 17sylanbrc 413 . 2  |-  ( ( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B )  ->  F : A --> B )
194, 18impbii 125 1  |-  ( F : A --> B  <->  ( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B
) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 103    <-> wb 104    = wceq 1316    e. wcel 1465   A.wral 2393   E.wrex 2394    C_ wss 3041   ran crn 4510    Fn wfn 5088   -->wf 5089   ` cfv 5093
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 683  ax-5 1408  ax-7 1409  ax-gen 1410  ax-ie1 1454  ax-ie2 1455  ax-8 1467  ax-10 1468  ax-11 1469  ax-i12 1470  ax-bndl 1471  ax-4 1472  ax-14 1477  ax-17 1491  ax-i9 1495  ax-ial 1499  ax-i5r 1500  ax-ext 2099  ax-sep 4016  ax-pow 4068  ax-pr 4101
This theorem depends on definitions:  df-bi 116  df-3an 949  df-tru 1319  df-nf 1422  df-sb 1721  df-eu 1980  df-mo 1981  df-clab 2104  df-cleq 2110  df-clel 2113  df-nfc 2247  df-ral 2398  df-rex 2399  df-v 2662  df-sbc 2883  df-un 3045  df-in 3047  df-ss 3054  df-pw 3482  df-sn 3503  df-pr 3504  df-op 3506  df-uni 3707  df-br 3900  df-opab 3960  df-mpt 3961  df-id 4185  df-xp 4515  df-rel 4516  df-cnv 4517  df-co 4518  df-dm 4519  df-rn 4520  df-iota 5058  df-fun 5095  df-fn 5096  df-f 5097  df-fv 5101
This theorem is referenced by:  ffnfvf  5547  fnfvrnss  5548  fmpt2d  5550  ffnov  5843  elixpconst  6568  elixpsn  6597  ctssdccl  6964  cnref1o  9396  shftf  10557  eff2  11300  reeff1  11321  dvfre  12754  isomninnlem  13121
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