Theorem cnvsn0 5848

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 5552	. . 3 ⊢ dom {∅} = ran ◡{∅}
2		dmsn0 5847	. . 3 ⊢ dom {∅} = ∅
3	1, 2	eqtr3i 2851	. 2 ⊢ ran ◡{∅} = ∅
4		relcnv 5748	. . 3 ⊢ Rel ◡{∅}
5		relrn0 5620	. . 3 ⊢ (Rel ◡{∅} → (◡{∅} = ∅ ↔ ran ◡{∅} = ∅))
6	4, 5	ax-mp 5	. 2 ⊢ (◡{∅} = ∅ ↔ ran ◡{∅} = ∅)
7	3, 6	mpbir 223	1 ⊢ ◡{∅} = ∅

Syntax hints:   ↔ wb 198   = wceq 1656  ∅c0 4146  {csn 4399  ^◡ccnv 5345  dom cdm 5346  ran crn 5347  Rel wrel 5351

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1894  ax-4 1908  ax-5 2009  ax-6 2075  ax-7 2112  ax-9 2173  ax-10 2192  ax-11 2207  ax-12 2220  ax-13 2389  ax-ext 2803  ax-sep 5007  ax-nul 5015  ax-pr 5129

This theorem depends on definitions:  df-bi 199  df-an 387  df-or 879  df-3an 1113  df-tru 1660  df-ex 1879  df-nf 1883  df-sb 2068  df-mo 2605  df-eu 2640  df-clab 2812  df-cleq 2818  df-clel 2821  df-nfc 2958  df-ne 3000  df-rab 3126  df-v 3416  df-dif 3801  df-un 3803  df-in 3805  df-ss 3812  df-nul 4147  df-if 4309  df-sn 4400  df-pr 4402  df-op 4406  df-br 4876  df-opab 4938  df-xp 5352  df-rel 5353  df-cnv 5354  df-dm 5356  df-rn 5357

This theorem is referenced by:  opswap  5867  brtpos0  7629  tpostpos  7642