Theorem brrelex1i 4718

Description: The first argument of a binary relation exists. (An artifact of our ordered pair definition.) (Contributed by NM, 4-Jun-1998.)

Hypothesis

Ref	Expression
brrelexi.1	⊢ Rel 𝑅

Assertion

Ref	Expression
brrelex1i	⊢ (𝐴𝑅𝐵 → 𝐴 ∈ V)

Proof of Theorem brrelex1i

Step	Hyp	Ref	Expression
1		brrelexi.1	. 2 ⊢ Rel 𝑅
2		brrelex1 4714	. 2 ⊢ ((Rel 𝑅 ∧ 𝐴𝑅𝐵) → 𝐴 ∈ V)
3	1, 2	mpan 424	1 ⊢ (𝐴𝑅𝐵 → 𝐴 ∈ V)

Syntax hints:   → wi 4   ∈ wcel 2176  Vcvv 2772   class class class wbr 4044  Rel wrel 4680

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 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-14 2179  ax-ext 2187  ax-sep 4162  ax-pow 4218  ax-pr 4253

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-nf 1484  df-sb 1786  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ral 2489  df-rex 2490  df-v 2774  df-un 3170  df-in 3172  df-ss 3179  df-pw 3618  df-sn 3639  df-pr 3640  df-op 3642  df-br 4045  df-opab 4106  df-xp 4681  df-rel 4682

This theorem is referenced by:  nprrel  4720  vtoclr  4723  opeliunxp2  4818  ideqg  4829  issetid  4832  fvmptss2  5654  opeliunxp2f  6324  brtpos2  6337  brdomg  6837  ctex  6842  isfi  6852  domssr  6869  en1uniel  6896  xpdom2  6926  xpdom1g  6928  xpen  6942  isbth  7069  djudom  7195  cc3  7380  aprcl  8719  climcl  11593  climi  11598  climrecl  11635  structex  12844