Theorem difxp 6153

Description: Difference of Cartesian products, expressed in terms of a union of Cartesian products of differences. (Contributed by Jeff Madsen, 2-Sep-2009.) (Revised by Mario Carneiro, 26-Jun-2014.) (Proof shortened by Wolf Lammen, 16-May-2025.)

Assertion

Ref	Expression
difxp	⊢ ((𝐶 × 𝐷) ∖ (𝐴 × 𝐵)) = (((𝐶 ∖ 𝐴) × 𝐷) ∪ (𝐶 × (𝐷 ∖ 𝐵)))

Proof of Theorem difxp

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		difss 4111	. . 3 ⊢ ((𝐶 × 𝐷) ∖ (𝐴 × 𝐵)) ⊆ (𝐶 × 𝐷)
2		relxp 5672	. . 3 ⊢ Rel (𝐶 × 𝐷)
3		relss 5760	. . 3 ⊢ (((𝐶 × 𝐷) ∖ (𝐴 × 𝐵)) ⊆ (𝐶 × 𝐷) → (Rel (𝐶 × 𝐷) → Rel ((𝐶 × 𝐷) ∖ (𝐴 × 𝐵))))
4	1, 2, 3	mp2 9	. 2 ⊢ Rel ((𝐶 × 𝐷) ∖ (𝐴 × 𝐵))
5		relxp 5672	. . 3 ⊢ Rel ((𝐶 ∖ 𝐴) × 𝐷)
6		relxp 5672	. . 3 ⊢ Rel (𝐶 × (𝐷 ∖ 𝐵))
7		relun 5790	. . 3 ⊢ (Rel (((𝐶 ∖ 𝐴) × 𝐷) ∪ (𝐶 × (𝐷 ∖ 𝐵))) ↔ (Rel ((𝐶 ∖ 𝐴) × 𝐷) ∧ Rel (𝐶 × (𝐷 ∖ 𝐵))))
8	5, 6, 7	mpbir2an 711	. 2 ⊢ Rel (((𝐶 ∖ 𝐴) × 𝐷) ∪ (𝐶 × (𝐷 ∖ 𝐵)))
9		ianor 983	. . . . . 6 ⊢ (¬ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) ↔ (¬ 𝑥 ∈ 𝐴 ∨ ¬ 𝑦 ∈ 𝐵))
10	9	anbi2i 623	. . . . 5 ⊢ (((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) ↔ ((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ (¬ 𝑥 ∈ 𝐴 ∨ ¬ 𝑦 ∈ 𝐵)))
11		andi 1009	. . . . 5 ⊢ (((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ (¬ 𝑥 ∈ 𝐴 ∨ ¬ 𝑦 ∈ 𝐵)) ↔ (((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ 𝑥 ∈ 𝐴) ∨ ((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ 𝑦 ∈ 𝐵)))
12	10, 11	bitri 275	. . . 4 ⊢ (((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) ↔ (((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ 𝑥 ∈ 𝐴) ∨ ((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ 𝑦 ∈ 𝐵)))
13		opelxp 5690	. . . . 5 ⊢ (⟨𝑥, 𝑦⟩ ∈ (𝐶 × 𝐷) ↔ (𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷))
14		opelxp 5690	. . . . . 6 ⊢ (⟨𝑥, 𝑦⟩ ∈ (𝐴 × 𝐵) ↔ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵))
15	14	notbii 320	. . . . 5 ⊢ (¬ ⟨𝑥, 𝑦⟩ ∈ (𝐴 × 𝐵) ↔ ¬ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵))
16	13, 15	anbi12i 628	. . . 4 ⊢ ((⟨𝑥, 𝑦⟩ ∈ (𝐶 × 𝐷) ∧ ¬ ⟨𝑥, 𝑦⟩ ∈ (𝐴 × 𝐵)) ↔ ((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)))
17		opelxp 5690	. . . . . 6 ⊢ (⟨𝑥, 𝑦⟩ ∈ ((𝐶 ∖ 𝐴) × 𝐷) ↔ (𝑥 ∈ (𝐶 ∖ 𝐴) ∧ 𝑦 ∈ 𝐷))
18		eldif 3936	. . . . . . 7 ⊢ (𝑥 ∈ (𝐶 ∖ 𝐴) ↔ (𝑥 ∈ 𝐶 ∧ ¬ 𝑥 ∈ 𝐴))
19	18	anbi1i 624	. . . . . 6 ⊢ ((𝑥 ∈ (𝐶 ∖ 𝐴) ∧ 𝑦 ∈ 𝐷) ↔ ((𝑥 ∈ 𝐶 ∧ ¬ 𝑥 ∈ 𝐴) ∧ 𝑦 ∈ 𝐷))
20		an32 646	. . . . . 6 ⊢ (((𝑥 ∈ 𝐶 ∧ ¬ 𝑥 ∈ 𝐴) ∧ 𝑦 ∈ 𝐷) ↔ ((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ 𝑥 ∈ 𝐴))
21	17, 19, 20	3bitri 297	. . . . 5 ⊢ (⟨𝑥, 𝑦⟩ ∈ ((𝐶 ∖ 𝐴) × 𝐷) ↔ ((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ 𝑥 ∈ 𝐴))
22		eldif 3936	. . . . . . 7 ⊢ (𝑦 ∈ (𝐷 ∖ 𝐵) ↔ (𝑦 ∈ 𝐷 ∧ ¬ 𝑦 ∈ 𝐵))
23	22	anbi2i 623	. . . . . 6 ⊢ ((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ (𝐷 ∖ 𝐵)) ↔ (𝑥 ∈ 𝐶 ∧ (𝑦 ∈ 𝐷 ∧ ¬ 𝑦 ∈ 𝐵)))
24		opelxp 5690	. . . . . 6 ⊢ (⟨𝑥, 𝑦⟩ ∈ (𝐶 × (𝐷 ∖ 𝐵)) ↔ (𝑥 ∈ 𝐶 ∧ 𝑦 ∈ (𝐷 ∖ 𝐵)))
25		anass 468	. . . . . 6 ⊢ (((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ 𝑦 ∈ 𝐵) ↔ (𝑥 ∈ 𝐶 ∧ (𝑦 ∈ 𝐷 ∧ ¬ 𝑦 ∈ 𝐵)))
26	23, 24, 25	3bitr4i 303	. . . . 5 ⊢ (⟨𝑥, 𝑦⟩ ∈ (𝐶 × (𝐷 ∖ 𝐵)) ↔ ((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ 𝑦 ∈ 𝐵))
27	21, 26	orbi12i 914	. . . 4 ⊢ ((⟨𝑥, 𝑦⟩ ∈ ((𝐶 ∖ 𝐴) × 𝐷) ∨ ⟨𝑥, 𝑦⟩ ∈ (𝐶 × (𝐷 ∖ 𝐵))) ↔ (((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ 𝑥 ∈ 𝐴) ∨ ((𝑥 ∈ 𝐶 ∧ 𝑦 ∈ 𝐷) ∧ ¬ 𝑦 ∈ 𝐵)))
28	12, 16, 27	3bitr4i 303	. . 3 ⊢ ((⟨𝑥, 𝑦⟩ ∈ (𝐶 × 𝐷) ∧ ¬ ⟨𝑥, 𝑦⟩ ∈ (𝐴 × 𝐵)) ↔ (⟨𝑥, 𝑦⟩ ∈ ((𝐶 ∖ 𝐴) × 𝐷) ∨ ⟨𝑥, 𝑦⟩ ∈ (𝐶 × (𝐷 ∖ 𝐵))))
29		eldif 3936	. . 3 ⊢ (⟨𝑥, 𝑦⟩ ∈ ((𝐶 × 𝐷) ∖ (𝐴 × 𝐵)) ↔ (⟨𝑥, 𝑦⟩ ∈ (𝐶 × 𝐷) ∧ ¬ ⟨𝑥, 𝑦⟩ ∈ (𝐴 × 𝐵)))
30		elun 4128	. . 3 ⊢ (⟨𝑥, 𝑦⟩ ∈ (((𝐶 ∖ 𝐴) × 𝐷) ∪ (𝐶 × (𝐷 ∖ 𝐵))) ↔ (⟨𝑥, 𝑦⟩ ∈ ((𝐶 ∖ 𝐴) × 𝐷) ∨ ⟨𝑥, 𝑦⟩ ∈ (𝐶 × (𝐷 ∖ 𝐵))))
31	28, 29, 30	3bitr4i 303	. 2 ⊢ (⟨𝑥, 𝑦⟩ ∈ ((𝐶 × 𝐷) ∖ (𝐴 × 𝐵)) ↔ ⟨𝑥, 𝑦⟩ ∈ (((𝐶 ∖ 𝐴) × 𝐷) ∪ (𝐶 × (𝐷 ∖ 𝐵))))
32	4, 8, 31	eqrelriiv 5769	1 ⊢ ((𝐶 × 𝐷) ∖ (𝐴 × 𝐵)) = (((𝐶 ∖ 𝐴) × 𝐷) ∪ (𝐶 × (𝐷 ∖ 𝐵)))

Syntax hints:  ¬ wn 3   ∧ wa 395   ∨ wo 847   = wceq 1540   ∈ wcel 2108   ∖ cdif 3923   ∪ cun 3924   ⊆ wss 3926  ⟨cop 4607   × cxp 5652  Rel wrel 5659

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 2007  ax-8 2110  ax-9 2118  ax-ext 2707  ax-sep 5266  ax-nul 5276  ax-pr 5402

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-sb 2065  df-clab 2714  df-cleq 2727  df-clel 2809  df-ral 3052  df-rex 3061  df-rab 3416  df-v 3461  df-dif 3929  df-un 3931  df-ss 3943  df-nul 4309  df-if 4501  df-sn 4602  df-pr 4604  df-op 4608  df-opab 5182  df-xp 5660  df-rel 5661

This theorem is referenced by:  difxp1  6154  difxp2  6155  evlslem4  22034  txcld  23541  suppovss  32658  elrgspnlem2  33238  elrgspnsubrunlem2  33243