| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | opelxp 5721 | . . 3
⊢
(〈〈𝐷,
𝐻〉, 𝐴〉 ∈ (({𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} × (𝒫 𝐸 ∩ Fin)) × 𝐸) ↔ (〈𝐷, 𝐻〉 ∈ ({𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} × (𝒫 𝐸 ∩ Fin)) ∧ 𝐴 ∈ 𝐸)) | 
| 2 |  | opelxp 5721 | . . . . 5
⊢
(〈𝐷, 𝐻〉 ∈ ({𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} × (𝒫 𝐸 ∩ Fin)) ↔ (𝐷 ∈ {𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} ∧ 𝐻 ∈ (𝒫 𝐸 ∩ Fin))) | 
| 3 |  | cnveq 5884 | . . . . . . . . 9
⊢ (𝑑 = 𝐷 → ◡𝑑 = ◡𝐷) | 
| 4 |  | id 22 | . . . . . . . . 9
⊢ (𝑑 = 𝐷 → 𝑑 = 𝐷) | 
| 5 | 3, 4 | eqeq12d 2753 | . . . . . . . 8
⊢ (𝑑 = 𝐷 → (◡𝑑 = 𝑑 ↔ ◡𝐷 = 𝐷)) | 
| 6 | 5 | elrab 3692 | . . . . . . 7
⊢ (𝐷 ∈ {𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} ↔ (𝐷 ∈ 𝒫 𝑉 ∧ ◡𝐷 = 𝐷)) | 
| 7 |  | mpstval.v | . . . . . . . . . 10
⊢ 𝑉 = (mDV‘𝑇) | 
| 8 | 7 | fvexi 6920 | . . . . . . . . 9
⊢ 𝑉 ∈ V | 
| 9 | 8 | elpw2 5334 | . . . . . . . 8
⊢ (𝐷 ∈ 𝒫 𝑉 ↔ 𝐷 ⊆ 𝑉) | 
| 10 | 9 | anbi1i 624 | . . . . . . 7
⊢ ((𝐷 ∈ 𝒫 𝑉 ∧ ◡𝐷 = 𝐷) ↔ (𝐷 ⊆ 𝑉 ∧ ◡𝐷 = 𝐷)) | 
| 11 | 6, 10 | bitri 275 | . . . . . 6
⊢ (𝐷 ∈ {𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} ↔ (𝐷 ⊆ 𝑉 ∧ ◡𝐷 = 𝐷)) | 
| 12 |  | elfpw 9394 | . . . . . 6
⊢ (𝐻 ∈ (𝒫 𝐸 ∩ Fin) ↔ (𝐻 ⊆ 𝐸 ∧ 𝐻 ∈ Fin)) | 
| 13 | 11, 12 | anbi12i 628 | . . . . 5
⊢ ((𝐷 ∈ {𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} ∧ 𝐻 ∈ (𝒫 𝐸 ∩ Fin)) ↔ ((𝐷 ⊆ 𝑉 ∧ ◡𝐷 = 𝐷) ∧ (𝐻 ⊆ 𝐸 ∧ 𝐻 ∈ Fin))) | 
| 14 | 2, 13 | bitri 275 | . . . 4
⊢
(〈𝐷, 𝐻〉 ∈ ({𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} × (𝒫 𝐸 ∩ Fin)) ↔ ((𝐷 ⊆ 𝑉 ∧ ◡𝐷 = 𝐷) ∧ (𝐻 ⊆ 𝐸 ∧ 𝐻 ∈ Fin))) | 
| 15 | 14 | anbi1i 624 | . . 3
⊢
((〈𝐷, 𝐻〉 ∈ ({𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} × (𝒫 𝐸 ∩ Fin)) ∧ 𝐴 ∈ 𝐸) ↔ (((𝐷 ⊆ 𝑉 ∧ ◡𝐷 = 𝐷) ∧ (𝐻 ⊆ 𝐸 ∧ 𝐻 ∈ Fin)) ∧ 𝐴 ∈ 𝐸)) | 
| 16 | 1, 15 | bitri 275 | . 2
⊢
(〈〈𝐷,
𝐻〉, 𝐴〉 ∈ (({𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} × (𝒫 𝐸 ∩ Fin)) × 𝐸) ↔ (((𝐷 ⊆ 𝑉 ∧ ◡𝐷 = 𝐷) ∧ (𝐻 ⊆ 𝐸 ∧ 𝐻 ∈ Fin)) ∧ 𝐴 ∈ 𝐸)) | 
| 17 |  | df-ot 4635 | . . 3
⊢
〈𝐷, 𝐻, 𝐴〉 = 〈〈𝐷, 𝐻〉, 𝐴〉 | 
| 18 |  | mpstval.e | . . . 4
⊢ 𝐸 = (mEx‘𝑇) | 
| 19 |  | mpstval.p | . . . 4
⊢ 𝑃 = (mPreSt‘𝑇) | 
| 20 | 7, 18, 19 | mpstval 35540 | . . 3
⊢ 𝑃 = (({𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} × (𝒫 𝐸 ∩ Fin)) × 𝐸) | 
| 21 | 17, 20 | eleq12i 2834 | . 2
⊢
(〈𝐷, 𝐻, 𝐴〉 ∈ 𝑃 ↔ 〈〈𝐷, 𝐻〉, 𝐴〉 ∈ (({𝑑 ∈ 𝒫 𝑉 ∣ ◡𝑑 = 𝑑} × (𝒫 𝐸 ∩ Fin)) × 𝐸)) | 
| 22 |  | df-3an 1089 | . 2
⊢ (((𝐷 ⊆ 𝑉 ∧ ◡𝐷 = 𝐷) ∧ (𝐻 ⊆ 𝐸 ∧ 𝐻 ∈ Fin) ∧ 𝐴 ∈ 𝐸) ↔ (((𝐷 ⊆ 𝑉 ∧ ◡𝐷 = 𝐷) ∧ (𝐻 ⊆ 𝐸 ∧ 𝐻 ∈ Fin)) ∧ 𝐴 ∈ 𝐸)) | 
| 23 | 16, 21, 22 | 3bitr4i 303 | 1
⊢
(〈𝐷, 𝐻, 𝐴〉 ∈ 𝑃 ↔ ((𝐷 ⊆ 𝑉 ∧ ◡𝐷 = 𝐷) ∧ (𝐻 ⊆ 𝐸 ∧ 𝐻 ∈ Fin) ∧ 𝐴 ∈ 𝐸)) |