Theorem ssexd 3918

Description: A subclass of a set is a set. Deduction form of ssexg 3917. (Contributed by David Moews, 1-May-2017.)

Hypotheses

Ref	Expression
ssexd.1	|- ( ph -> B e. C )
ssexd.2	|- ( ph -> A C_ B )

Assertion

Ref	Expression
ssexd	|- ( ph -> A e. _V )

Proof of Theorem ssexd

Step	Hyp	Ref	Expression
1		ssexd.2	. 2 |- ( ph -> A C_ B )
2		ssexd.1	. 2 |- ( ph -> B e. C )
3		ssexg 3917	. 2 |- ( ( A C_ B /\ B e. C ) -> A e. _V )
4	1, 2, 3	syl2anc 403	1 |- ( ph -> A e. _V )

Syntax hints:   -> wi 4   e. wcel 1433   _Vcvv 2601   C_ wss 2973

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-io 662  ax-5 1376  ax-7 1377  ax-gen 1378  ax-ie1 1422  ax-ie2 1423  ax-8 1435  ax-10 1436  ax-11 1437  ax-i12 1438  ax-bndl 1439  ax-4 1440  ax-17 1459  ax-i9 1463  ax-ial 1467  ax-i5r 1468  ax-ext 2063  ax-sep 3896

This theorem depends on definitions:  df-bi 115  df-tru 1287  df-nf 1390  df-sb 1686  df-clab 2068  df-cleq 2074  df-clel 2077  df-nfc 2208  df-v 2603  df-in 2979  df-ss 2986

This theorem is referenced by:  fex2  5079  riotaexg  5492  opabbrex  5569  f1imaen2g  6296  genipv  6699  iseqss  9446  ovshftex  9707