Theorem relrn0 4809

Description: A relation is empty iff its range is empty. (Contributed by NM, 15-Sep-2004.)

Assertion

Ref	Expression
relrn0	|- ( Rel A -> ( A = (/) <-> ran A = (/) ) )

Proof of Theorem relrn0

Step	Hyp	Ref	Expression
1		reldm0 4765	. 2 |- ( Rel A -> ( A = (/) <-> dom A = (/) ) )
2		dm0rn0 4764	. 2 |- ( dom A = (/) <-> ran A = (/) )
3	1, 2	syl6bb 195	1 |- ( Rel A -> ( A = (/) <-> ran A = (/) ) )

Syntax hints:   -> wi 4   <-> wb 104   = wceq 1332   (/)c0 3368   dom cdm 4547   ran crn 4548   Rel wrel 4552

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 604  ax-in2 605  ax-io 699  ax-5 1424  ax-7 1425  ax-gen 1426  ax-ie1 1470  ax-ie2 1471  ax-8 1483  ax-10 1484  ax-11 1485  ax-i12 1486  ax-bndl 1487  ax-4 1488  ax-14 1493  ax-17 1507  ax-i9 1511  ax-ial 1515  ax-i5r 1516  ax-ext 2122  ax-sep 4054  ax-pow 4106  ax-pr 4139

This theorem depends on definitions:  df-bi 116  df-3an 965  df-tru 1335  df-fal 1338  df-nf 1438  df-sb 1737  df-eu 2003  df-mo 2004  df-clab 2127  df-cleq 2133  df-clel 2136  df-nfc 2271  df-v 2691  df-dif 3078  df-un 3080  df-in 3082  df-ss 3089  df-nul 3369  df-pw 3517  df-sn 3538  df-pr 3539  df-op 3541  df-br 3938  df-opab 3998  df-xp 4553  df-rel 4554  df-cnv 4555  df-dm 4557  df-rn 4558

This theorem is referenced by:  cnvsn0  5015