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Theorem ffnfv 5351
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 5074 . . 3  |-  ( F : A --> B  ->  F  Fn  A )
2 ffvelrn 5328 . . . 4  |-  ( ( F : A --> B  /\  x  e.  A )  ->  ( F `  x
)  e.  B )
32ralrimiva 2409 . . 3  |-  ( F : A --> B  ->  A. x  e.  A  ( F `  x )  e.  B )
41, 3jca 294 . 2  |-  ( F : A --> B  -> 
( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B ) )
5 simpl 106 . . 3  |-  ( ( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B )  ->  F  Fn  A )
6 fvelrnb 5249 . . . . . 6  |-  ( F  Fn  A  ->  (
y  e.  ran  F  <->  E. x  e.  A  ( F `  x )  =  y ) )
76biimpd 136 . . . . 5  |-  ( F  Fn  A  ->  (
y  e.  ran  F  ->  E. x  e.  A  ( F `  x )  =  y ) )
8 nfra1 2372 . . . . . 6  |-  F/ x A. x  e.  A  ( F `  x )  e.  B
9 nfv 1437 . . . . . 6  |-  F/ x  y  e.  B
10 rsp 2386 . . . . . . 7  |-  ( A. x  e.  A  ( F `  x )  e.  B  ->  ( x  e.  A  ->  ( F `  x )  e.  B ) )
11 eleq1 2116 . . . . . . . 8  |-  ( ( F `  x )  =  y  ->  (
( F `  x
)  e.  B  <->  y  e.  B ) )
1211biimpcd 152 . . . . . . 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 2447 . . . . 5  |-  ( A. x  e.  A  ( F `  x )  e.  B  ->  ( E. x  e.  A  ( F `  x )  =  y  ->  y  e.  B ) )
157, 14sylan9 395 . . . 4  |-  ( ( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B )  -> 
( y  e.  ran  F  ->  y  e.  B
) )
1615ssrdv 2979 . . 3  |-  ( ( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B )  ->  ran  F  C_  B )
17 df-f 4934 . . 3  |-  ( F : A --> B  <->  ( F  Fn  A  /\  ran  F  C_  B ) )
185, 16, 17sylanbrc 402 . 2  |-  ( ( F  Fn  A  /\  A. x  e.  A  ( F `  x )  e.  B )  ->  F : A --> B )
194, 18impbii 121 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 101    <-> wb 102    = wceq 1259    e. wcel 1409   A.wral 2323   E.wrex 2324    C_ wss 2945   ran crn 4374    Fn wfn 4925   -->wf 4926   ` cfv 4930
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 103  ax-ia2 104  ax-ia3 105  ax-io 640  ax-5 1352  ax-7 1353  ax-gen 1354  ax-ie1 1398  ax-ie2 1399  ax-8 1411  ax-10 1412  ax-11 1413  ax-i12 1414  ax-bndl 1415  ax-4 1416  ax-14 1421  ax-17 1435  ax-i9 1439  ax-ial 1443  ax-i5r 1444  ax-ext 2038  ax-sep 3903  ax-pow 3955  ax-pr 3972
This theorem depends on definitions:  df-bi 114  df-3an 898  df-tru 1262  df-nf 1366  df-sb 1662  df-eu 1919  df-mo 1920  df-clab 2043  df-cleq 2049  df-clel 2052  df-nfc 2183  df-ral 2328  df-rex 2329  df-v 2576  df-sbc 2788  df-un 2950  df-in 2952  df-ss 2959  df-pw 3389  df-sn 3409  df-pr 3410  df-op 3412  df-uni 3609  df-br 3793  df-opab 3847  df-mpt 3848  df-id 4058  df-xp 4379  df-rel 4380  df-cnv 4381  df-co 4382  df-dm 4383  df-rn 4384  df-iota 4895  df-fun 4932  df-fn 4933  df-f 4934  df-fv 4938
This theorem is referenced by:  ffnfvf  5352  fnfvrnss  5353  fmpt2d  5355  ffnov  5633  cnref1o  8680  iseqf  9388  shftf  9659
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