Theorem inintabd 42315

Description: Value of the intersection of class with the intersection of a nonempty class. (Contributed by RP, 13-Aug-2020.)

Hypothesis

Ref	Expression
inintabd.x	⊢ (𝜑 → ∃𝑥𝜓)

Assertion

Ref	Expression
inintabd	⊢ (𝜑 → (𝐴 ∩ ∩ {𝑥 ∣ 𝜓}) = ∩ {𝑤 ∈ 𝒫 𝐴 ∣ ∃𝑥(𝑤 = (𝐴 ∩ 𝑥) ∧ 𝜓)})

Distinct variable groups:   𝜓,𝑤   𝑥,𝑤,𝐴

Allowed substitution hints:   𝜑(𝑥,𝑤)   𝜓(𝑥)

Proof of Theorem inintabd

Dummy variable 𝑢 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		inintabd.x	. . . . . 6 ⊢ (𝜑 → ∃𝑥𝜓)
2		pm5.5 361	. . . . . 6 ⊢ (∃𝑥𝜓 → ((∃𝑥𝜓 → 𝑢 ∈ 𝐴) ↔ 𝑢 ∈ 𝐴))
3	1, 2	syl 17	. . . . 5 ⊢ (𝜑 → ((∃𝑥𝜓 → 𝑢 ∈ 𝐴) ↔ 𝑢 ∈ 𝐴))
4	3	bicomd 222	. . . 4 ⊢ (𝜑 → (𝑢 ∈ 𝐴 ↔ (∃𝑥𝜓 → 𝑢 ∈ 𝐴)))
5	4	anbi1d 630	. . 3 ⊢ (𝜑 → ((𝑢 ∈ 𝐴 ∧ ∀𝑥(𝜓 → 𝑢 ∈ 𝑥)) ↔ ((∃𝑥𝜓 → 𝑢 ∈ 𝐴) ∧ ∀𝑥(𝜓 → 𝑢 ∈ 𝑥))))
6		elinintab 42311	. . 3 ⊢ (𝑢 ∈ (𝐴 ∩ ∩ {𝑥 ∣ 𝜓}) ↔ (𝑢 ∈ 𝐴 ∧ ∀𝑥(𝜓 → 𝑢 ∈ 𝑥)))
7		elinintrab 42313	. . . 4 ⊢ (𝑢 ∈ V → (𝑢 ∈ ∩ {𝑤 ∈ 𝒫 𝐴 ∣ ∃𝑥(𝑤 = (𝐴 ∩ 𝑥) ∧ 𝜓)} ↔ ((∃𝑥𝜓 → 𝑢 ∈ 𝐴) ∧ ∀𝑥(𝜓 → 𝑢 ∈ 𝑥))))
8	7	elv 3480	. . 3 ⊢ (𝑢 ∈ ∩ {𝑤 ∈ 𝒫 𝐴 ∣ ∃𝑥(𝑤 = (𝐴 ∩ 𝑥) ∧ 𝜓)} ↔ ((∃𝑥𝜓 → 𝑢 ∈ 𝐴) ∧ ∀𝑥(𝜓 → 𝑢 ∈ 𝑥)))
9	5, 6, 8	3bitr4g 313	. 2 ⊢ (𝜑 → (𝑢 ∈ (𝐴 ∩ ∩ {𝑥 ∣ 𝜓}) ↔ 𝑢 ∈ ∩ {𝑤 ∈ 𝒫 𝐴 ∣ ∃𝑥(𝑤 = (𝐴 ∩ 𝑥) ∧ 𝜓)}))
10	9	eqrdv 2730	1 ⊢ (𝜑 → (𝐴 ∩ ∩ {𝑥 ∣ 𝜓}) = ∩ {𝑤 ∈ 𝒫 𝐴 ∣ ∃𝑥(𝑤 = (𝐴 ∩ 𝑥) ∧ 𝜓)})

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 396  ∀wal 1539   = wceq 1541  ∃wex 1781   ∈ wcel 2106  {cab 2709  {crab 3432  Vcvv 3474   ∩ cin 3946  𝒫 cpw 4601  ∩ cint 4949

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2703  ax-sep 5298

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 846  df-tru 1544  df-ex 1782  df-nf 1786  df-sb 2068  df-clab 2710  df-cleq 2724  df-clel 2810  df-ral 3062  df-rex 3071  df-rab 3433  df-v 3476  df-in 3954  df-ss 3964  df-pw 4603  df-int 4950

This theorem is referenced by:  xpinintabd  42316