Theorem prdsbasex 17504

Description: Lemma for structure products. (Contributed by Mario Carneiro, 3-Jan-2015.)

Hypothesis

Ref	Expression
prdsbasex.b	⊢ 𝐵 = X𝑥 ∈ dom 𝑅(Base‘(𝑅‘𝑥))

Assertion

Ref	Expression
prdsbasex	⊢ 𝐵 ∈ V

Distinct variable group:   𝑥,𝑅

Allowed substitution hint:   𝐵(𝑥)

Proof of Theorem prdsbasex

Step	Hyp	Ref	Expression
1		prdsbasex.b	. 2 ⊢ 𝐵 = X𝑥 ∈ dom 𝑅(Base‘(𝑅‘𝑥))
2		ixpexg 8921	. . 3 ⊢ (∀𝑥 ∈ dom 𝑅(Base‘(𝑅‘𝑥)) ∈ V → X𝑥 ∈ dom 𝑅(Base‘(𝑅‘𝑥)) ∈ V)
3		fvexd 6898	. . 3 ⊢ (𝑥 ∈ dom 𝑅 → (Base‘(𝑅‘𝑥)) ∈ V)
4	2, 3	mprg 3085	. 2 ⊢ X𝑥 ∈ dom 𝑅(Base‘(𝑅‘𝑥)) ∈ V
5	1, 4	eqeltri 2859	1 ⊢ 𝐵 ∈ V

Syntax hints:   = wceq 1570   ∈ wcel 2143  Vcvv 3455  dom cdm 5663  ‘cfv 6538  Xcixp 8896  Basecbs 17270

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1825  ax-4 1839  ax-5 1940  ax-6 1997  ax-7 2038  ax-8 2145  ax-9 2153  ax-10 2176  ax-11 2192  ax-12 2213  ax-ext 2735  ax-rep 5239  ax-sep 5258  ax-nul 5270  ax-pow 5338  ax-pr 5406  ax-un 7734

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1810  df-nf 1814  df-sb 2097  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2838  df-nfc 2912  df-ne 2959  df-ral 3080  df-rex 3090  df-rab 3417  df-v 3457  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-nul 4288  df-if 4489  df-pw 4565  df-sn 4591  df-pr 4593  df-op 4597  df-uni 4874  df-iun 4959  df-br 5111  df-opab 5175  df-mpt 5194  df-id 5558  df-xp 5669  df-rel 5670  df-cnv 5671  df-co 5672  df-dm 5673  df-rn 5674  df-iota 6494  df-fun 6540  df-fn 6541  df-f 6542  df-fv 6546  df-ixp 8897

This theorem is referenced by: (None)