Theorem restin 13947

Description: When the subspace region is not a subset of the base of the topology, the resulting set is the same as the subspace restricted to the base. (Contributed by Mario Carneiro, 15-Dec-2013.)

Hypothesis

Ref	Expression
restin.1	⊢ 𝑋 = ∪ 𝐽

Assertion

Ref	Expression
restin	⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → (𝐽 ↾t 𝐴) = (𝐽 ↾t (𝐴 ∩ 𝑋)))

Proof of Theorem restin

Step	Hyp	Ref	Expression
1		restin.1	. . . . 5 ⊢ 𝑋 = ∪ 𝐽
2		uniexg 4451	. . . . 5 ⊢ (𝐽 ∈ 𝑉 → ∪ 𝐽 ∈ V)
3	1, 2	eqeltrid 2274	. . . 4 ⊢ (𝐽 ∈ 𝑉 → 𝑋 ∈ V)
4	3	adantr 276	. . 3 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → 𝑋 ∈ V)
5		restco 13945	. . . 4 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝑋 ∈ V ∧ 𝐴 ∈ 𝑊) → ((𝐽 ↾t 𝑋) ↾t 𝐴) = (𝐽 ↾t (𝑋 ∩ 𝐴)))
6	5	3com23 1210	. . 3 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊 ∧ 𝑋 ∈ V) → ((𝐽 ↾t 𝑋) ↾t 𝐴) = (𝐽 ↾t (𝑋 ∩ 𝐴)))
7	4, 6	mpd3an3 1348	. 2 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → ((𝐽 ↾t 𝑋) ↾t 𝐴) = (𝐽 ↾t (𝑋 ∩ 𝐴)))
8	1	restid 12716	. . . 4 ⊢ (𝐽 ∈ 𝑉 → (𝐽 ↾t 𝑋) = 𝐽)
9	8	adantr 276	. . 3 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → (𝐽 ↾t 𝑋) = 𝐽)
10	9	oveq1d 5903	. 2 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → ((𝐽 ↾t 𝑋) ↾t 𝐴) = (𝐽 ↾t 𝐴))
11		incom 3339	. . . 4 ⊢ (𝑋 ∩ 𝐴) = (𝐴 ∩ 𝑋)
12	11	oveq2i 5899	. . 3 ⊢ (𝐽 ↾t (𝑋 ∩ 𝐴)) = (𝐽 ↾t (𝐴 ∩ 𝑋))
13	12	a1i 9	. 2 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → (𝐽 ↾t (𝑋 ∩ 𝐴)) = (𝐽 ↾t (𝐴 ∩ 𝑋)))
14	7, 10, 13	3eqtr3d 2228	1 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → (𝐽 ↾t 𝐴) = (𝐽 ↾t (𝐴 ∩ 𝑋)))

Syntax hints:   → wi 4   ∧ wa 104   = wceq 1363   ∈ wcel 2158  Vcvv 2749   ∩ cin 3140  ∪ cuni 3821  (class class class)co 5888   ↾_t crest 12705

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-in1 615  ax-in2 616  ax-io 710  ax-5 1457  ax-7 1458  ax-gen 1459  ax-ie1 1503  ax-ie2 1504  ax-8 1514  ax-10 1515  ax-11 1516  ax-i12 1517  ax-bndl 1519  ax-4 1520  ax-17 1536  ax-i9 1540  ax-ial 1544  ax-i5r 1545  ax-13 2160  ax-14 2161  ax-ext 2169  ax-coll 4130  ax-sep 4133  ax-pow 4186  ax-pr 4221  ax-un 4445  ax-setind 4548

This theorem depends on definitions:  df-bi 117  df-3an 981  df-tru 1366  df-fal 1369  df-nf 1471  df-sb 1773  df-eu 2039  df-mo 2040  df-clab 2174  df-cleq 2180  df-clel 2183  df-nfc 2318  df-ne 2358  df-ral 2470  df-rex 2471  df-reu 2472  df-rab 2474  df-v 2751  df-sbc 2975  df-csb 3070  df-dif 3143  df-un 3145  df-in 3147  df-ss 3154  df-pw 3589  df-sn 3610  df-pr 3611  df-op 3613  df-uni 3822  df-iun 3900  df-br 4016  df-opab 4077  df-mpt 4078  df-id 4305  df-xp 4644  df-rel 4645  df-cnv 4646  df-co 4647  df-dm 4648  df-rn 4649  df-res 4650  df-ima 4651  df-iota 5190  df-fun 5230  df-fn 5231  df-f 5232  df-f1 5233  df-fo 5234  df-f1o 5235  df-fv 5236  df-ov 5891  df-oprab 5892  df-mpo 5893  df-1st 6154  df-2nd 6155  df-rest 12707

This theorem is referenced by:  restuni2  13948  cnrest2r  14008