Theorem bdciun 13913

Description: The indexed union of a bounded class with a setvar indexing set is a bounded class. (Contributed by BJ, 16-Oct-2019.)

Hypothesis

Ref	Expression
bdciun.1	⊢ BOUNDED 𝐴

Assertion

Ref	Expression
bdciun	⊢ BOUNDED ∪ 𝑥 ∈ 𝑦 𝐴

Distinct variable group:   𝑥,𝑦

Allowed substitution hints:   𝐴(𝑥,𝑦)

Proof of Theorem bdciun

Dummy variable 𝑧 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		bdciun.1	. . . . 5 ⊢ BOUNDED 𝐴
2	1	bdeli 13881	. . . 4 ⊢ BOUNDED 𝑧 ∈ 𝐴
3	2	ax-bdex 13854	. . 3 ⊢ BOUNDED ∃𝑥 ∈ 𝑦 𝑧 ∈ 𝐴
4	3	bdcab 13884	. 2 ⊢ BOUNDED {𝑧 ∣ ∃𝑥 ∈ 𝑦 𝑧 ∈ 𝐴}
5		df-iun 3875	. 2 ⊢ ∪ 𝑥 ∈ 𝑦 𝐴 = {𝑧 ∣ ∃𝑥 ∈ 𝑦 𝑧 ∈ 𝐴}
6	4, 5	bdceqir 13879	1 ⊢ BOUNDED ∪ 𝑥 ∈ 𝑦 𝐴

Syntax hints:   ∈ wcel 2141  {cab 2156  ∃wrex 2449  ∪ ciun 3873  BOUNDED wbdc 13875

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1440  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-4 1503  ax-17 1519  ax-ial 1527  ax-ext 2152  ax-bd0 13848  ax-bdex 13854  ax-bdsb 13857

This theorem depends on definitions:  df-bi 116  df-clab 2157  df-cleq 2163  df-clel 2166  df-iun 3875  df-bdc 13876

This theorem is referenced by: (None)