Theorem ideq 4871

Description: For sets, the identity relation is the same as equality. (Contributed by NM, 13-Aug-1995.)

Hypothesis

Ref	Expression
ideq.1	⊢ 𝐵 ∈ V

Assertion

Ref	Expression
ideq	⊢ (𝐴 I 𝐵 ↔ 𝐴 = 𝐵)

Proof of Theorem ideq

Step	Hyp	Ref	Expression
1		ideq.1	. 2 ⊢ 𝐵 ∈ V
2		ideqg 4870	. 2 ⊢ (𝐵 ∈ V → (𝐴 I 𝐵 ↔ 𝐴 = 𝐵))
3	1, 2	ax-mp 5	1 ⊢ (𝐴 I 𝐵 ↔ 𝐴 = 𝐵)

Syntax hints:   ↔ wb 105   = wceq 1395   ∈ wcel 2200  Vcvv 2799   class class class wbr 4082   I cid 4376

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 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-14 2203  ax-ext 2211  ax-sep 4201  ax-pow 4257  ax-pr 4292

This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ral 2513  df-rex 2514  df-v 2801  df-un 3201  df-in 3203  df-ss 3210  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-br 4083  df-opab 4145  df-id 4381  df-xp 4722  df-rel 4723

This theorem is referenced by:  dmi  4935  resieq  5011  resiexg  5046  iss  5047  restidsing  5057  imai  5080  issref  5107  intasym  5109  asymref  5110  intirr  5111  poirr2  5117  cnvi  5129  coi1  5240  idssen  6918