Theorem rescnvcnv 5230

Description: The restriction of the double converse of a class. (Contributed by NM, 8-Apr-2007.) (Proof shortened by Andrew Salmon, 27-Aug-2011.)

Assertion

Ref	Expression
rescnvcnv	⊢ (◡◡𝐴 ↾ 𝐵) = (𝐴 ↾ 𝐵)

Proof of Theorem rescnvcnv

Step	Hyp	Ref	Expression
1		cnvcnv2 5221	. . 3 ⊢ ◡◡𝐴 = (𝐴 ↾ V)
2	1	reseq1i 5039	. 2 ⊢ (◡◡𝐴 ↾ 𝐵) = ((𝐴 ↾ V) ↾ 𝐵)
3		resres 5055	. 2 ⊢ ((𝐴 ↾ V) ↾ 𝐵) = (𝐴 ↾ (V ∩ 𝐵))
4		ssv 3264	. . . 4 ⊢ 𝐵 ⊆ V
5		sseqin2 3444	. . . 4 ⊢ (𝐵 ⊆ V ↔ (V ∩ 𝐵) = 𝐵)
6	4, 5	mpbi 145	. . 3 ⊢ (V ∩ 𝐵) = 𝐵
7	6	reseq2i 5040	. 2 ⊢ (𝐴 ↾ (V ∩ 𝐵)) = (𝐴 ↾ 𝐵)
8	2, 3, 7	3eqtri 2259	1 ⊢ (◡◡𝐴 ↾ 𝐵) = (𝐴 ↾ 𝐵)

Syntax hints:   = wceq 1398  Vcvv 2815   ∩ cin 3213   ⊆ wss 3214  ^◡ccnv 4753   ↾ cres 4756

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 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-14 2208  ax-ext 2216  ax-sep 4233  ax-pow 4292  ax-pr 4327

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1812  df-eu 2085  df-mo 2086  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-ral 2527  df-rex 2528  df-v 2817  df-un 3218  df-in 3220  df-ss 3227  df-pw 3676  df-sn 3700  df-pr 3701  df-op 3703  df-br 4115  df-opab 4177  df-xp 4760  df-rel 4761  df-cnv 4762  df-res 4766

This theorem is referenced by:  cnvcnvres  5231  imacnvcnv  5232  resdm2  5258  resdmres  5259  coires1  5285  cocnvres  5292  f1oresrab  5847