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Theorem elfvm 5609
Description: If a function value has a member, the function is inhabited. (Contributed by Jim Kingdon, 14-Jun-2025.)
Assertion
Ref Expression
elfvm  |-  ( A  e.  ( F `  B )  ->  E. j 
j  e.  F )
Distinct variable group:    j, F
Allowed substitution hints:    A( j)    B( j)

Proof of Theorem elfvm
Dummy variables  k  x are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eliotaeu 5260 . . . 4  |-  ( A  e.  ( iota x B F x )  ->  E! x  B F x )
2 df-fv 5279 . . . 4  |-  ( F `
 B )  =  ( iota x B F x )
31, 2eleq2s 2300 . . 3  |-  ( A  e.  ( F `  B )  ->  E! x  B F x )
4 euex 2084 . . 3  |-  ( E! x  B F x  ->  E. x  B F x )
5 brm 4094 . . . 4  |-  ( B F x  ->  E. k 
k  e.  F )
65exlimiv 1621 . . 3  |-  ( E. x  B F x  ->  E. k  k  e.  F )
73, 4, 63syl 17 . 2  |-  ( A  e.  ( F `  B )  ->  E. k 
k  e.  F )
8 eleq1w 2266 . . 3  |-  ( k  =  j  ->  (
k  e.  F  <->  j  e.  F ) )
98cbvexv 1942 . 2  |-  ( E. k  k  e.  F  <->  E. j  j  e.  F
)
107, 9sylib 122 1  |-  ( A  e.  ( F `  B )  ->  E. j 
j  e.  F )
Colors of variables: wff set class
Syntax hints:    -> wi 4   E.wex 1515   E!weu 2054    e. wcel 2176   class class class wbr 4044   iotacio 5230   ` cfv 5271
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 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-ext 2187
This theorem depends on definitions:  df-bi 117  df-tru 1376  df-nf 1484  df-sb 1786  df-eu 2057  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-rex 2490  df-v 2774  df-sn 3639  df-uni 3851  df-br 4045  df-iota 5232  df-fv 5279
This theorem is referenced by:  basm  12893
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