Theorem restin 23122

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 7695	. . . . 5 ⊢ (𝐽 ∈ 𝑉 → ∪ 𝐽 ∈ V)
3	1, 2	eqeltrid 2841	. . . 4 ⊢ (𝐽 ∈ 𝑉 → 𝑋 ∈ V)
4	3	adantr 480	. . 3 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → 𝑋 ∈ V)
5		restco 23120	. . . 4 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝑋 ∈ V ∧ 𝐴 ∈ 𝑊) → ((𝐽 ↾t 𝑋) ↾t 𝐴) = (𝐽 ↾t (𝑋 ∩ 𝐴)))
6	5	3com23 1127	. . 3 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊 ∧ 𝑋 ∈ V) → ((𝐽 ↾t 𝑋) ↾t 𝐴) = (𝐽 ↾t (𝑋 ∩ 𝐴)))
7	4, 6	mpd3an3 1465	. 2 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → ((𝐽 ↾t 𝑋) ↾t 𝐴) = (𝐽 ↾t (𝑋 ∩ 𝐴)))
8	1	restid 17365	. . . 4 ⊢ (𝐽 ∈ 𝑉 → (𝐽 ↾t 𝑋) = 𝐽)
9	8	adantr 480	. . 3 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → (𝐽 ↾t 𝑋) = 𝐽)
10	9	oveq1d 7383	. 2 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → ((𝐽 ↾t 𝑋) ↾t 𝐴) = (𝐽 ↾t 𝐴))
11		incom 4163	. . . 4 ⊢ (𝑋 ∩ 𝐴) = (𝐴 ∩ 𝑋)
12	11	oveq2i 7379	. . 3 ⊢ (𝐽 ↾t (𝑋 ∩ 𝐴)) = (𝐽 ↾t (𝐴 ∩ 𝑋))
13	12	a1i 11	. 2 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → (𝐽 ↾t (𝑋 ∩ 𝐴)) = (𝐽 ↾t (𝐴 ∩ 𝑋)))
14	7, 10, 13	3eqtr3d 2780	1 ⊢ ((𝐽 ∈ 𝑉 ∧ 𝐴 ∈ 𝑊) → (𝐽 ↾t 𝐴) = (𝐽 ↾t (𝐴 ∩ 𝑋)))

Syntax hints:   → wi 4   ∧ wa 395   = wceq 1542   ∈ wcel 2114  Vcvv 3442   ∩ cin 3902  ∪ cuni 4865  (class class class)co 7368   ↾_t crest 17352

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2709  ax-rep 5226  ax-sep 5243  ax-nul 5253  ax-pow 5312  ax-pr 5379  ax-un 7690

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2540  df-eu 2570  df-clab 2716  df-cleq 2729  df-clel 2812  df-nfc 2886  df-ne 2934  df-ral 3053  df-rex 3063  df-reu 3353  df-rab 3402  df-v 3444  df-sbc 3743  df-csb 3852  df-dif 3906  df-un 3908  df-in 3910  df-ss 3920  df-nul 4288  df-if 4482  df-pw 4558  df-sn 4583  df-pr 4585  df-op 4589  df-uni 4866  df-iun 4950  df-br 5101  df-opab 5163  df-mpt 5182  df-id 5527  df-xp 5638  df-rel 5639  df-cnv 5640  df-co 5641  df-dm 5642  df-rn 5643  df-res 5644  df-ima 5645  df-iota 6456  df-fun 6502  df-fn 6503  df-f 6504  df-f1 6505  df-fo 6506  df-f1o 6507  df-fv 6508  df-ov 7371  df-oprab 7372  df-mpo 7373  df-rest 17354

This theorem is referenced by:  restuni2  23123  cnrest2r  23243  cnrmi  23316  restcnrm  23318  resthauslem  23319  imacmp  23353  fiuncmp  23360  kgeni  23493  ressxms  24481  ptrest  37864  restuni6  45475