Theorem iunex 6287

Description: The existence of an indexed union. 𝑥 is normally a free-variable parameter in the class expression substituted for 𝐵, which can be read informally as 𝐵(𝑥). (Contributed by NM, 13-Oct-2003.)

Hypotheses

Ref	Expression
iunex.1	⊢ 𝐴 ∈ V
iunex.2	⊢ 𝐵 ∈ V

Assertion

Ref	Expression
iunex	⊢ ∪ 𝑥 ∈ 𝐴 𝐵 ∈ V

Distinct variable group:   𝑥,𝐴

Allowed substitution hint:   𝐵(𝑥)

Proof of Theorem iunex

Step	Hyp	Ref	Expression
1		iunex.1	. 2 ⊢ 𝐴 ∈ V
2		iunex.2	. . 3 ⊢ 𝐵 ∈ V
3	2	rgenw 2586	. 2 ⊢ ∀𝑥 ∈ 𝐴 𝐵 ∈ V
4		iunexg 6283	. 2 ⊢ ((𝐴 ∈ V ∧ ∀𝑥 ∈ 𝐴 𝐵 ∈ V) → ∪ 𝑥 ∈ 𝐴 𝐵 ∈ V)
5	1, 3, 4	mp2an 426	1 ⊢ ∪ 𝑥 ∈ 𝐴 𝐵 ∈ V

Syntax hints:   ∈ wcel 2201  ∀wral 2509  Vcvv 2801  ∪ ciun 3969

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-13 2203  ax-14 2204  ax-ext 2212  ax-coll 4203  ax-sep 4206  ax-pow 4263  ax-pr 4298  ax-un 4529

This theorem depends on definitions:  df-bi 117  df-3an 1006  df-tru 1400  df-nf 1509  df-sb 1810  df-eu 2081  df-mo 2082  df-clab 2217  df-cleq 2223  df-clel 2226  df-nfc 2362  df-ral 2514  df-rex 2515  df-reu 2516  df-rab 2518  df-v 2803  df-sbc 3031  df-csb 3127  df-un 3203  df-in 3205  df-ss 3212  df-pw 3653  df-sn 3674  df-pr 3675  df-op 3677  df-uni 3893  df-iun 3971  df-br 4088  df-opab 4150  df-mpt 4151  df-id 4389  df-xp 4730  df-rel 4731  df-cnv 4732  df-co 4733  df-dm 4734  df-rn 4735  df-res 4736  df-ima 4737  df-iota 5285  df-fun 5327  df-fn 5328  df-f 5329  df-f1 5330  df-fo 5331  df-f1o 5332  df-fv 5333

This theorem is referenced by:  abrexex2  6288