Theorem inundif 4434

Description: The intersection and class difference of a class with another class unite to give the original class. (Contributed by Paul Chapman, 5-Jun-2009.) (Proof shortened by Andrew Salmon, 26-Jun-2011.)

Assertion

Ref	Expression
inundif	⊢ ((𝐴 ∩ 𝐵) ∪ (𝐴 ∖ 𝐵)) = 𝐴

Proof of Theorem inundif

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		elin 4092	. . . 4 ⊢ (𝑥 ∈ (𝐴 ∩ 𝐵) ↔ (𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵))
2		eldif 4048	. . . 4 ⊢ (𝑥 ∈ (𝐴 ∖ 𝐵) ↔ (𝑥 ∈ 𝐴 ∧ ¬ 𝑥 ∈ 𝐵))
3	1, 2	orbi12i 928	. . 3 ⊢ ((𝑥 ∈ (𝐴 ∩ 𝐵) ∨ 𝑥 ∈ (𝐴 ∖ 𝐵)) ↔ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∨ (𝑥 ∈ 𝐴 ∧ ¬ 𝑥 ∈ 𝐵)))
4		pm4.42 1069	. . 3 ⊢ (𝑥 ∈ 𝐴 ↔ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ 𝐵) ∨ (𝑥 ∈ 𝐴 ∧ ¬ 𝑥 ∈ 𝐵)))
5	3, 4	bitr4i 281	. 2 ⊢ ((𝑥 ∈ (𝐴 ∩ 𝐵) ∨ 𝑥 ∈ (𝐴 ∖ 𝐵)) ↔ 𝑥 ∈ 𝐴)
6	5	uneqri 4154	1 ⊢ ((𝐴 ∩ 𝐵) ∪ (𝐴 ∖ 𝐵)) = 𝐴

This proof depends on syntax axioms:  ¬ wn 3   ∧ wa 401   ∨ wo 861   = wceq 1569   ∈ wcel 2144   ∖ cdif 4044   ∩ cin 4088   ∪ cun 4148

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-ext 2732

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-tru 1572  df-ex 1812  df-sb 2099  df-clab 2739  df-cleq 2752  df-clel 2835  df-v 3452  df-dif 4046  df-in 4090  df-un 4150

This theorem is used by:  iunxdif3  5054  partfun  6691  resasplit  6757  fresaun  6758  fresaunres2  6759  ixpfi2  9346  hashun3  14535  prmreclem2  17104  mvdco  19668  sylow2a  19842  ablfac1eu  20298  basdif0  23280  neitr  23507  cmpfi  23735  ptbasfi  23909  ptcnplem  23949  fin1aufil  24260  ismbl2  25857  volinun  25876  voliunlem2  25881  mbfeqalem2  25972  itg2cnlem2  26092  dvres2lem  26239  indifundif  33171  imadifxp  33246  ofpreima2  33311  resf1o  33372  indsumin  33478  gsummptres  33663  tocyccntz  33755  measun  34894  measunl  34899  inelcarsg  34993  carsgclctun  35003  sibfof  35022  probdif  35102  hgt750lemd  35327  mthmpps  36437  clcnvlem  44732  radcnvrat  45407  sumnnodd  46750  ovolsplit  47106  omelesplit  47636  ovnsplit  47766