Theorem iunexg 7987

Description: The existence of an indexed union. 𝑥 is normally a free-variable parameter in 𝐵. (Contributed by NM, 23-Mar-2006.)

Assertion

Ref	Expression
iunexg	⊢ ((𝐴 ∈ 𝑉 ∧ ∀𝑥 ∈ 𝐴 𝐵 ∈ 𝑊) → ∪ 𝑥 ∈ 𝐴 𝐵 ∈ V)

Distinct variable group:   𝑥,𝐴

Allowed substitution hints:   𝐵(𝑥)   𝑉(𝑥)   𝑊(𝑥)

Proof of Theorem iunexg

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		dfiun2g 5035	. . 3 ⊢ (∀𝑥 ∈ 𝐴 𝐵 ∈ 𝑊 → ∪ 𝑥 ∈ 𝐴 𝐵 = ∪ {𝑦 ∣ ∃𝑥 ∈ 𝐴 𝑦 = 𝐵})
2	1	adantl 481	. 2 ⊢ ((𝐴 ∈ 𝑉 ∧ ∀𝑥 ∈ 𝐴 𝐵 ∈ 𝑊) → ∪ 𝑥 ∈ 𝐴 𝐵 = ∪ {𝑦 ∣ ∃𝑥 ∈ 𝐴 𝑦 = 𝐵})
3		abrexexg 7984	. . . 4 ⊢ (𝐴 ∈ 𝑉 → {𝑦 ∣ ∃𝑥 ∈ 𝐴 𝑦 = 𝐵} ∈ V)
4	3	uniexd 7761	. . 3 ⊢ (𝐴 ∈ 𝑉 → ∪ {𝑦 ∣ ∃𝑥 ∈ 𝐴 𝑦 = 𝐵} ∈ V)
5	4	adantr 480	. 2 ⊢ ((𝐴 ∈ 𝑉 ∧ ∀𝑥 ∈ 𝐴 𝐵 ∈ 𝑊) → ∪ {𝑦 ∣ ∃𝑥 ∈ 𝐴 𝑦 = 𝐵} ∈ V)
6	2, 5	eqeltrd 2839	1 ⊢ ((𝐴 ∈ 𝑉 ∧ ∀𝑥 ∈ 𝐴 𝐵 ∈ 𝑊) → ∪ 𝑥 ∈ 𝐴 𝐵 ∈ V)

Syntax hints:   → wi 4   ∧ wa 395   = wceq 1537   ∈ wcel 2106  {cab 2712  ∀wral 3059  ∃wrex 3068  Vcvv 3478  ∪ cuni 4912  ∪ ciun 4996

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1792  ax-4 1806  ax-5 1908  ax-6 1965  ax-7 2005  ax-8 2108  ax-9 2116  ax-11 2155  ax-ext 2706  ax-rep 5285  ax-sep 5302  ax-un 7754

This theorem depends on definitions:  df-bi 207  df-an 396  df-tru 1540  df-ex 1777  df-sb 2063  df-mo 2538  df-clab 2713  df-cleq 2727  df-clel 2814  df-ral 3060  df-rex 3069  df-v 3480  df-ss 3980  df-uni 4913  df-iun 4998

This theorem is referenced by:  abrexex2g  7988  opabex3d  7989  opabex3rd  7990  opabex3  7991  iunex  7992  xpexgALT  8005  mpoexxg  8099  ixpexg  8961  ixpssmapg  8967  ttrclselem2  9764  iundom  10580  iunctb  10612  wrdexg  14559  cshwsex  17135  imasplusg  17564  imasmulr  17565  imasvsca  17567  imasip  17568  gsum2d2  20007  gsumcom2  20008  dprd2da  20077  ptcls  23640  ptcmplem2  24077  elpwiuncl  32555  aciunf1lem  32679  gsumpart  33043  gsumwrd2dccat  33053  irngval  33700  esum2dlem  34073  esum2d  34074  esumiun  34075  omssubadd  34282  eulerpartlemgs2  34362  bnj535  34883  bnj546  34889  bnj893  34921  bnj1136  34990  bnj1413  35028  weiunse  36451  numiunnum  36453  eliunov2  43669  fvmptiunrelexplb0d  43674  fvmptiunrelexplb1d  43676  iunrelexp0  43692  collexd  44253  unirnmapsn  45157  iunmapss  45158  ssmapsn  45159  iunmapsn  45160  sge0iunmptlemfi  46369  sge0iunmpt  46374  smflimlem1  46727  smfliminflem  46786  mpoexxg2  48183