Theorem elfvfvex 5673

Description: If a function value is inhabited, the function value is a set. (Contributed by Jim Kingdon, 30-Jan-2026.)

Assertion

Ref	Expression
elfvfvex	|- ( A e. ( F ` B ) -> ( F ` B ) e. _V )

Proof of Theorem elfvfvex

Dummy variable w is distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-fv 5334	. 2 |- ( F ` B ) = ( iota w B F w )
2		eliotaeu 5315	. . . 4 |- ( A e. ( iota w B F w ) -> E! w B F w )
3	2, 1	eleq2s 2326	. . 3 |- ( A e. ( F ` B ) -> E! w B F w )
4		euiotaex 5303	. . 3 |- ( E! w B F w -> ( iota w B F w ) e. _V )
5	3, 4	syl 14	. 2 |- ( A e. ( F ` B ) -> ( iota w B F w ) e. _V )
6	1, 5	eqeltrid 2318	1 |- ( A e. ( F ` B ) -> ( F ` B ) e. _V )

Syntax hints:   -> wi 4   E!weu 2079   e. wcel 2202   _Vcvv 2802   class class class wbr 4088   iotacio 5284   ` 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-ext 2213

This theorem depends on definitions:  df-bi 117  df-tru 1400  df-nf 1509  df-sb 1811  df-eu 2082  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-rex 2516  df-v 2804  df-sbc 3032  df-un 3204  df-sn 3675  df-pr 3676  df-uni 3894  df-iota 5286  df-fv 5334

This theorem is referenced by:  fvmbr  5674  wlkvtxiedg  16195  wlkvtxiedgg  16196