Theorem brrelex2 4700

Description: A true binary relation on a relation implies the second argument is a set. (This is a property of our ordered pair definition.) (Contributed by Mario Carneiro, 26-Apr-2015.)

Assertion

Ref	Expression
brrelex2	|- ( ( Rel R /\ A R B ) -> B e. _V )

Proof of Theorem brrelex2

Step	Hyp	Ref	Expression
1		brrelex12 4697	. 2 |- ( ( Rel R /\ A R B ) -> ( A e. _V /\ B e. _V ) )
2	1	simprd 114	1 |- ( ( Rel R /\ A R B ) -> B e. _V )

Syntax hints:   -> wi 4   /\ wa 104   e. wcel 2164   _Vcvv 2760   class class class wbr 4029   Rel wrel 4664

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 710  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-14 2167  ax-ext 2175  ax-sep 4147  ax-pow 4203  ax-pr 4238

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-nf 1472  df-sb 1774  df-clab 2180  df-cleq 2186  df-clel 2189  df-nfc 2325  df-ral 2477  df-rex 2478  df-v 2762  df-un 3157  df-in 3159  df-ss 3166  df-pw 3603  df-sn 3624  df-pr 3625  df-op 3627  df-br 4030  df-opab 4091  df-xp 4665  df-rel 4666

This theorem is referenced by:  brrelex2i  4703  releldm  4897  relelrn  4898  elrelimasn  5031  funbrfv  5595  ertr  6602  erth  6633