Theorem cnvsn0 6199

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 5875	. . 3 ⊢ dom {∅} = ran ◡{∅}
2		dmsn0 6198	. . 3 ⊢ dom {∅} = ∅
3	1, 2	eqtr3i 2760	. 2 ⊢ ran ◡{∅} = ∅
4		relcnv 6091	. . 3 ⊢ Rel ◡{∅}
5		relrn0 5952	. . 3 ⊢ (Rel ◡{∅} → (◡{∅} = ∅ ↔ ran ◡{∅} = ∅))
6	4, 5	ax-mp 5	. 2 ⊢ (◡{∅} = ∅ ↔ ran ◡{∅} = ∅)
7	3, 6	mpbir 231	1 ⊢ ◡{∅} = ∅

Syntax hints:   ↔ wb 206   = wceq 1540  ∅c0 4308  {csn 4601  ^◡ccnv 5653  dom cdm 5654  ran crn 5655  Rel wrel 5659

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2007  ax-8 2110  ax-9 2118  ax-10 2141  ax-11 2157  ax-12 2177  ax-ext 2707  ax-sep 5266  ax-nul 5276  ax-pr 5402

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1543  df-fal 1553  df-ex 1780  df-nf 1784  df-sb 2065  df-clab 2714  df-cleq 2727  df-clel 2809  df-ne 2933  df-rab 3416  df-v 3461  df-dif 3929  df-un 3931  df-ss 3943  df-nul 4309  df-if 4501  df-sn 4602  df-pr 4604  df-op 4608  df-br 5120  df-opab 5182  df-xp 5660  df-rel 5661  df-cnv 5662  df-dm 5664  df-rn 5665

This theorem is referenced by:  opswap  6218  brtpos0  8232  tpostpos  8245  dftpos5  48849