Theorem ideq 4927

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 4926	. 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 1402   ∈ wcel 2209  Vcvv 2821   class class class wbr 4125   I cid 4428

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 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4244  ax-pow 4306  ax-pr 4341

This theorem depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ral 2533  df-rex 2534  df-v 2823  df-un 3224  df-in 3226  df-ss 3233  df-pw 3687  df-sn 3711  df-pr 3712  df-op 3714  df-br 4126  df-opab 4188  df-id 4433  df-xp 4775  df-rel 4776

This theorem is referenced by:  dmi  4991  resieq  5068  resiexg  5103  iss  5104  restidsing  5114  imai  5138  issref  5165  intasym  5167  asymref  5168  intirr  5169  poirr2  5175  cnvi  5187  coi1  5298  idssen  7053