Theorem reseq2 4879

Description: Equality theorem for restrictions. (Contributed by NM, 8-Aug-1994.)

Assertion

Ref	Expression
reseq2	⊢ (𝐴 = 𝐵 → (𝐶 ↾ 𝐴) = (𝐶 ↾ 𝐵))

Proof of Theorem reseq2

Step	Hyp	Ref	Expression
1		xpeq1 4618	. . 3 ⊢ (𝐴 = 𝐵 → (𝐴 × V) = (𝐵 × V))
2	1	ineq2d 3323	. 2 ⊢ (𝐴 = 𝐵 → (𝐶 ∩ (𝐴 × V)) = (𝐶 ∩ (𝐵 × V)))
3		df-res 4616	. 2 ⊢ (𝐶 ↾ 𝐴) = (𝐶 ∩ (𝐴 × V))
4		df-res 4616	. 2 ⊢ (𝐶 ↾ 𝐵) = (𝐶 ∩ (𝐵 × V))
5	2, 3, 4	3eqtr4g 2224	1 ⊢ (𝐴 = 𝐵 → (𝐶 ↾ 𝐴) = (𝐶 ↾ 𝐵))

Syntax hints:   → wi 4   = wceq 1343  Vcvv 2726   ∩ cin 3115   × cxp 4602   ↾ cres 4606

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147

This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-v 2728  df-in 3122  df-opab 4044  df-xp 4610  df-res 4616

This theorem is referenced by:  reseq2i  4881  reseq2d  4884  resabs1  4913  resima2  4918  imaeq2  4942  resdisj  5032  relcoi1  5135  fressnfv  5672  tfrlem1  6276  tfrlem9  6287  tfr0dm  6290  tfrlemisucaccv  6293  tfrlemiubacc  6298  tfr1onlemsucaccv  6309  tfr1onlemubacc  6314  tfr1onlemaccex  6316  tfrcllemsucaccv  6322  tfrcllembxssdm  6324  tfrcllemubacc  6327  tfrcllemaccex  6329  tfrcllemres  6330  tfrcldm  6331  fnfi  6902  lmbr2  12864  lmff  12899