Theorem qusin 17507

Description: Restrict the equivalence relation in a quotient structure to the base set. (Contributed by Mario Carneiro, 23-Feb-2015.)

Hypotheses

Ref	Expression
qusin.u	⊢ (𝜑 → 𝑈 = (𝑅 /s ∼ ))
qusin.v	⊢ (𝜑 → 𝑉 = (Base‘𝑅))
qusin.e	⊢ (𝜑 → ∼ ∈ 𝑊)
qusin.r	⊢ (𝜑 → 𝑅 ∈ 𝑍)
qusin.s	⊢ (𝜑 → ( ∼ “ 𝑉) ⊆ 𝑉)

Assertion

Ref	Expression
qusin	⊢ (𝜑 → 𝑈 = (𝑅 /s ( ∼ ∩ (𝑉 × 𝑉))))

Proof of Theorem qusin

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		qusin.s	. . . . 5 ⊢ (𝜑 → ( ∼ “ 𝑉) ⊆ 𝑉)
2		ecinxp 8765	. . . . 5 ⊢ ((( ∼ “ 𝑉) ⊆ 𝑉 ∧ 𝑥 ∈ 𝑉) → [𝑥] ∼ = [𝑥]( ∼ ∩ (𝑉 × 𝑉)))
3	1, 2	sylan 580	. . . 4 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝑉) → [𝑥] ∼ = [𝑥]( ∼ ∩ (𝑉 × 𝑉)))
4	3	mpteq2dva 5200	. . 3 ⊢ (𝜑 → (𝑥 ∈ 𝑉 ↦ [𝑥] ∼ ) = (𝑥 ∈ 𝑉 ↦ [𝑥]( ∼ ∩ (𝑉 × 𝑉))))
5	4	oveq1d 7402	. 2 ⊢ (𝜑 → ((𝑥 ∈ 𝑉 ↦ [𝑥] ∼ ) “s 𝑅) = ((𝑥 ∈ 𝑉 ↦ [𝑥]( ∼ ∩ (𝑉 × 𝑉))) “s 𝑅))
6		qusin.u	. . 3 ⊢ (𝜑 → 𝑈 = (𝑅 /s ∼ ))
7		qusin.v	. . 3 ⊢ (𝜑 → 𝑉 = (Base‘𝑅))
8		eqid 2729	. . 3 ⊢ (𝑥 ∈ 𝑉 ↦ [𝑥] ∼ ) = (𝑥 ∈ 𝑉 ↦ [𝑥] ∼ )
9		qusin.e	. . 3 ⊢ (𝜑 → ∼ ∈ 𝑊)
10		qusin.r	. . 3 ⊢ (𝜑 → 𝑅 ∈ 𝑍)
11	6, 7, 8, 9, 10	qusval 17505	. 2 ⊢ (𝜑 → 𝑈 = ((𝑥 ∈ 𝑉 ↦ [𝑥] ∼ ) “s 𝑅))
12		eqidd 2730	. . 3 ⊢ (𝜑 → (𝑅 /s ( ∼ ∩ (𝑉 × 𝑉))) = (𝑅 /s ( ∼ ∩ (𝑉 × 𝑉))))
13		eqid 2729	. . 3 ⊢ (𝑥 ∈ 𝑉 ↦ [𝑥]( ∼ ∩ (𝑉 × 𝑉))) = (𝑥 ∈ 𝑉 ↦ [𝑥]( ∼ ∩ (𝑉 × 𝑉)))
14		inex1g 5274	. . . 4 ⊢ ( ∼ ∈ 𝑊 → ( ∼ ∩ (𝑉 × 𝑉)) ∈ V)
15	9, 14	syl 17	. . 3 ⊢ (𝜑 → ( ∼ ∩ (𝑉 × 𝑉)) ∈ V)
16	12, 7, 13, 15, 10	qusval 17505	. 2 ⊢ (𝜑 → (𝑅 /s ( ∼ ∩ (𝑉 × 𝑉))) = ((𝑥 ∈ 𝑉 ↦ [𝑥]( ∼ ∩ (𝑉 × 𝑉))) “s 𝑅))
17	5, 11, 16	3eqtr4d 2774	1 ⊢ (𝜑 → 𝑈 = (𝑅 /s ( ∼ ∩ (𝑉 × 𝑉))))

Syntax hints:   → wi 4   = wceq 1540   ∈ wcel 2109  Vcvv 3447   ∩ cin 3913   ⊆ wss 3914   ↦ cmpt 5188   × cxp 5636   “ cima 5641  ‘cfv 6511  (class class class)co 7387  [cec 8669  Basecbs 17179   “_s cimas 17467   /_s cqus 17468

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-10 2142  ax-11 2158  ax-12 2178  ax-ext 2701  ax-sep 5251  ax-nul 5261  ax-pr 5387

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1543  df-fal 1553  df-ex 1780  df-nf 1784  df-sb 2066  df-mo 2533  df-eu 2562  df-clab 2708  df-cleq 2721  df-clel 2803  df-nfc 2878  df-ne 2926  df-ral 3045  df-rex 3054  df-rab 3406  df-v 3449  df-sbc 3754  df-dif 3917  df-un 3919  df-in 3921  df-ss 3931  df-nul 4297  df-if 4489  df-sn 4590  df-pr 4592  df-op 4596  df-uni 4872  df-br 5108  df-opab 5170  df-mpt 5189  df-id 5533  df-xp 5644  df-rel 5645  df-cnv 5646  df-co 5647  df-dm 5648  df-rn 5649  df-res 5650  df-ima 5651  df-iota 6464  df-fun 6513  df-fv 6519  df-ov 7390  df-oprab 7391  df-mpo 7392  df-ec 8673  df-qus 17472

This theorem is referenced by:  pi1addf  24947  pi1addval  24948  pi1grplem  24949