Theorem ecss 6349

Description: An equivalence class is a subset of the domain. (Contributed by NM, 6-Aug-1995.) (Revised by Mario Carneiro, 12-Aug-2015.)

Hypothesis

Ref	Expression
ecss.1	|- ( ph -> R Er X )

Assertion

Ref	Expression
ecss	|- ( ph -> [ A ] R C_ X )

Proof of Theorem ecss

Step	Hyp	Ref	Expression
1		df-ec 6310	. . 3 |- [ A ] R = ( R " { A } )
2		imassrn 4800	. . 3 |- ( R " { A } ) C_ ran R
3	1, 2	eqsstri 3059	. 2 |- [ A ] R C_ ran R
4		ecss.1	. . 3 |- ( ph -> R Er X )
5		errn 6330	. . 3 |- ( R Er X -> ran R = X )
6	4, 5	syl 14	. 2 |- ( ph -> ran R = X )
7	3, 6	syl5sseq 3077	1 |- ( ph -> [ A ] R C_ X )

Syntax hints:   -> wi 4   = wceq 1290   C_ wss 3002   {csn 3452   ran crn 4455   "cima 4457   Er wer 6305   [cec 6306

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 666  ax-5 1382  ax-7 1383  ax-gen 1384  ax-ie1 1428  ax-ie2 1429  ax-8 1441  ax-10 1442  ax-11 1443  ax-i12 1444  ax-bndl 1445  ax-4 1446  ax-14 1451  ax-17 1465  ax-i9 1469  ax-ial 1473  ax-i5r 1474  ax-ext 2071  ax-sep 3965  ax-pow 4017  ax-pr 4047

This theorem depends on definitions:  df-bi 116  df-3an 927  df-tru 1293  df-nf 1396  df-sb 1694  df-eu 1952  df-mo 1953  df-clab 2076  df-cleq 2082  df-clel 2085  df-nfc 2218  df-ral 2365  df-rex 2366  df-v 2624  df-un 3006  df-in 3008  df-ss 3015  df-pw 3437  df-sn 3458  df-pr 3459  df-op 3461  df-br 3854  df-opab 3908  df-xp 4460  df-rel 4461  df-cnv 4462  df-dm 4464  df-rn 4465  df-res 4466  df-ima 4467  df-er 6308  df-ec 6310

This theorem is referenced by:  qsss  6367