Theorem elpw 3655

Description: Membership in a power class. Theorem 86 of [Suppes] p. 47. (Contributed by NM, 31-Dec-1993.)

Hypothesis

Ref	Expression
elpw.1	|- A e. _V

Assertion

Ref	Expression
elpw	|- ( A e. ~P B <-> A C_ B )

Proof of Theorem elpw

Dummy variable x is distinct from all other variables.

Step	Hyp	Ref	Expression
1		elpw.1	. 2 |- A e. _V
2		sseq1 3247	. 2 |- ( x = A -> ( x C_ B <-> A C_ B ) )
3		df-pw 3651	. 2 |- ~P B = { x | x C_ B }
4	1, 2, 3	elab2 2951	1 |- ( A e. ~P B <-> A C_ B )

Syntax hints:   <-> wb 105   e. wcel 2200   _Vcvv 2799   C_ wss 3197   ~Pcpw 3649

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 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-ext 2211

This theorem depends on definitions:  df-bi 117  df-tru 1398  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-v 2801  df-in 3203  df-ss 3210  df-pw 3651

This theorem is referenced by:  velpw  3656  elpwg  3657  prsspw  3843  pwprss  3884  pwtpss  3885  pwv  3887  sspwuni  4050  iinpw  4056  iunpwss  4057  0elpw  4248  pwuni  4276  snelpw  4298  sspwb  4302  ssextss  4306  pwin  4373  pwunss  4374  iunpw  4571  xpsspw  4831  ssenen  7020  pw1ne3  7426  3nsssucpw1  7432  ioof  10179  tgdom  14761  distop  14774  epttop  14779  resttopon  14860  txuni2  14945  umgrbien  15925  umgredg  15958