Theorem cnvsn0 6211

Description: The converse of the singleton of the empty set is empty. (Contributed by Mario Carneiro, 30-Aug-2015.)

Assertion

Ref	Expression
cnvsn0	⊢ ◡{∅} = ∅

Proof of Theorem cnvsn0

Step	Hyp	Ref	Expression
1		dfdm4 5885	. . 3 ⊢ dom {∅} = ran ◡{∅}
2		dmsn0 6210	. . 3 ⊢ dom {∅} = ∅
3	1, 2	eqtr3i 2788	. 2 ⊢ ran ◡{∅} = ∅
4		relcnv 6106	. . 3 ⊢ Rel ◡{∅}
5		relrn0 5963	. . 3 ⊢ (Rel ◡{∅} → (◡{∅} = ∅ ↔ ran ◡{∅} = ∅))
6	4, 5	ax-mp 5	. 2 ⊢ (◡{∅} = ∅ ↔ ran ◡{∅} = ∅)
7	3, 6	mpbir 234	1 ⊢ ◡{∅} = ∅

Syntax hints:   ↔ wb 209   = wceq 1570  ∅c0 4286  {csn 4589  ^◡ccnv 5660  dom cdm 5661  ran crn 5662  Rel wrel 5666

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1825  ax-4 1839  ax-5 1940  ax-6 1997  ax-7 2038  ax-8 2145  ax-9 2153  ax-ext 2735  ax-sep 5257  ax-pr 5404

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1810  df-sb 2097  df-clab 2742  df-cleq 2755  df-clel 2838  df-ne 2959  df-rab 3417  df-v 3457  df-dif 3908  df-un 3910  df-in 3912  df-ss 3922  df-nul 4287  df-if 4488  df-sn 4590  df-pr 4592  df-op 4596  df-br 5110  df-opab 5174  df-xp 5667  df-rel 5668  df-cnv 5669  df-dm 5671  df-rn 5672

This theorem is referenced by:  opswap  6230  brtpos0  8225  tpostpos  8238  dftpos5  49672