Theorem dmcnvcnv 4981

Description: The domain of the double converse of a class (which doesn't have to be a relation as in dfrel2 5213). (Contributed by NM, 8-Apr-2007.)

Assertion

Ref	Expression
dmcnvcnv	|- dom `' `' A = dom A

Proof of Theorem dmcnvcnv

Step	Hyp	Ref	Expression
1		dfdm4 4948	. 2 |- dom A = ran `' A
2		df-rn 4760	. 2 |- ran `' A = dom `' `' A
3	1, 2	eqtr2i 2254	1 |- dom `' `' A = dom A

Syntax hints:   = wceq 1398   `'ccnv 4748   dom cdm 4749   ran crn 4750

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 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-14 2206  ax-ext 2214  ax-sep 4228  ax-pow 4287  ax-pr 4322

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1812  df-eu 2083  df-mo 2084  df-clab 2219  df-cleq 2225  df-clel 2228  df-nfc 2373  df-v 2815  df-un 3215  df-in 3217  df-ss 3224  df-pw 3671  df-sn 3695  df-pr 3696  df-op 3698  df-br 4110  df-opab 4172  df-cnv 4757  df-dm 4759  df-rn 4760

This theorem is referenced by:  resdm2  5253  f1cnvcnv  5584