Theorem lssmex 14664

Description: If a linear subspace is inhabited, the class it is built from is a set. (Contributed by Jim Kingdon, 28-Apr-2025.)

Hypothesis

Ref	Expression
lssmex.s	|- S = ( LSubSp ` W )

Assertion

Ref	Expression
lssmex	|- ( U e. S -> W e. _V )

Proof of Theorem lssmex

Dummy variables a b j s w x are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		mptrel 4903	. . . 4 |- Rel ( w e. _V |-> { s e. ~P ( Base ` w ) | ( E. j j e. s /\ A. x e. ( Base ` (Scalar ` w ) ) A. a e. s A. b e. s ( ( x ( .s ` w ) a ) ( +g ` w ) b ) e. s ) } )
2		df-lssm 14662	. . . . 5 |- LSubSp = ( w e. _V |-> { s e. ~P ( Base ` w ) | ( E. j j e. s /\ A. x e. ( Base ` (Scalar ` w ) ) A. a e. s A. b e. s ( ( x ( .s ` w ) a ) ( +g ` w ) b ) e. s ) } )
3	2	releqi 4853	. . . 4 |- ( Rel LSubSp <-> Rel ( w e. _V |-> { s e. ~P ( Base ` w ) | ( E. j j e. s /\ A. x e. ( Base ` (Scalar ` w ) ) A. a e. s A. b e. s ( ( x ( .s ` w ) a ) ( +g ` w ) b ) e. s ) } ) )
4	1, 3	mpbir 146	. . 3 |- Rel LSubSp
5		lssmex.s	. . . . 5 |- S = ( LSubSp ` W )
6	5	eleq2i 2305	. . . 4 |- ( U e. S <-> U e. ( LSubSp ` W ) )
7	6	biimpi 120	. . 3 |- ( U e. S -> U e. ( LSubSp ` W ) )
8		relelfvdm 5722	. . 3 |- ( ( Rel LSubSp /\ U e. ( LSubSp ` W ) ) -> W e. dom LSubSp )
9	4, 7, 8	sylancr 418	. 2 |- ( U e. S -> W e. dom LSubSp )
10	9	elexd 2835	1 |- ( U e. S -> W e. _V )

Syntax hints:   -> wi 4   /\ wa 104   = wceq 1402   E.wex 1545   e. wcel 2209   A.wral 2528   {crab 2532   _Vcvv 2821   ~Pcpw 3685   |-> cmpt 4187   dom cdm 4769   Rel wrel 4774   ` cfv 5372  (class class class)co 6075   Basecbs 13330   +g cplusg 13408  Scalarcsca 13411   .scvsca 13412   LSubSpclss 14661

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 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4244  ax-pow 4306  ax-pr 4341

This theorem depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ral 2533  df-rex 2534  df-v 2823  df-un 3224  df-in 3226  df-ss 3233  df-pw 3687  df-sn 3711  df-pr 3712  df-op 3714  df-uni 3931  df-br 4126  df-opab 4188  df-mpt 4189  df-xp 4775  df-rel 4776  df-dm 4779  df-iota 5332  df-fv 5380  df-lssm 14662

This theorem is referenced by:  islssm  14666