Theorem idinxpresid 6039

Description: The intersection of the identity relation with the cartesian square of a class is the restriction of the identity relation to that class. (Contributed by FL, 2-Aug-2009.) (Proof shortened by Peter Mazsa, 9-Sep-2022.) (Proof shortened by BJ, 23-Dec-2023.)

Assertion

Ref	Expression
idinxpresid	⊢ ( I ∩ (𝐴 × 𝐴)) = ( I ↾ 𝐴)

Proof of Theorem idinxpresid

Step	Hyp	Ref	Expression
1		idinxpres 6038	. 2 ⊢ ( I ∩ (𝐴 × 𝐴)) = ( I ↾ (𝐴 ∩ 𝐴))
2		inidm 4180	. . 3 ⊢ (𝐴 ∩ 𝐴) = 𝐴
3	2	reseq2i 5964	. 2 ⊢ ( I ↾ (𝐴 ∩ 𝐴)) = ( I ↾ 𝐴)
4	1, 3	eqtri 2787	1 ⊢ ( I ∩ (𝐴 × 𝐴)) = ( I ↾ 𝐴)

Syntax hints:   = wceq 1562   ∩ cin 3905   I cid 5543   × cxp 5647   ↾ cres 5651

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1817  ax-4 1831  ax-5 1932  ax-6 1989  ax-7 2030  ax-8 2146  ax-9 2154  ax-ext 2736  ax-sep 5248  ax-pr 5392

This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-3an 1101  df-tru 1565  df-fal 1575  df-ex 1802  df-sb 2093  df-clab 2743  df-cleq 2756  df-clel 2839  df-ral 3079  df-rex 3089  df-rab 3417  df-v 3458  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-nul 4288  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-br 5103  df-opab 5165  df-id 5544  df-xp 5655  df-rel 5656  df-res 5661

This theorem is referenced by:  idssxp  6040  bj-diagval2  37672  idinxpssinxp2  38828