| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | mdegle0.f | . . 3
⊢ (𝜑 → 𝐹 ∈ 𝐵) | 
| 2 |  | 0xr 11308 | . . 3
⊢ 0 ∈
ℝ* | 
| 3 |  | mdegaddle.d | . . . 4
⊢ 𝐷 = (𝐼 mDeg 𝑅) | 
| 4 |  | mdegaddle.y | . . . 4
⊢ 𝑌 = (𝐼 mPoly 𝑅) | 
| 5 |  | mdegle0.b | . . . 4
⊢ 𝐵 = (Base‘𝑌) | 
| 6 |  | eqid 2737 | . . . 4
⊢
(0g‘𝑅) = (0g‘𝑅) | 
| 7 |  | eqid 2737 | . . . 4
⊢ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} = {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈
Fin} | 
| 8 |  | eqid 2737 | . . . 4
⊢ (𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏)) = (𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏)) | 
| 9 | 3, 4, 5, 6, 7, 8 | mdegleb 26103 | . . 3
⊢ ((𝐹 ∈ 𝐵 ∧ 0 ∈ ℝ*) →
((𝐷‘𝐹) ≤ 0 ↔ ∀𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} (0 < ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) → (𝐹‘𝑥) = (0g‘𝑅)))) | 
| 10 | 1, 2, 9 | sylancl 586 | . 2
⊢ (𝜑 → ((𝐷‘𝐹) ≤ 0 ↔ ∀𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} (0 < ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) → (𝐹‘𝑥) = (0g‘𝑅)))) | 
| 11 | 7, 8 | tdeglem1 26097 | . . . . . . . . . 10
⊢ (𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏)):{𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈
Fin}⟶ℕ0 | 
| 12 | 11 | a1i 11 | . . . . . . . . 9
⊢ (𝜑 → (𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏)):{𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈
Fin}⟶ℕ0) | 
| 13 | 12 | ffvelcdmda 7104 | . . . . . . . 8
⊢ ((𝜑 ∧ 𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin}) → ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ∈
ℕ0) | 
| 14 |  | nn0re 12535 | . . . . . . . . 9
⊢ (((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ∈ ℕ0 → ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ∈ ℝ) | 
| 15 |  | nn0ge0 12551 | . . . . . . . . 9
⊢ (((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ∈ ℕ0 → 0 ≤
((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥)) | 
| 16 | 14, 15 | jca 511 | . . . . . . . 8
⊢ (((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ∈ ℕ0 → (((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ∈ ℝ ∧ 0 ≤ ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥))) | 
| 17 |  | ne0gt0 11366 | . . . . . . . 8
⊢ ((((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ∈ ℝ ∧ 0 ≤ ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥)) → (((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ≠ 0 ↔ 0 < ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥))) | 
| 18 | 13, 16, 17 | 3syl 18 | . . . . . . 7
⊢ ((𝜑 ∧ 𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin}) →
(((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ≠ 0 ↔ 0 < ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥))) | 
| 19 | 7, 8 | tdeglem4 26099 | . . . . . . . . 9
⊢ (𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} → (((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) = 0 ↔ 𝑥 = (𝐼 × {0}))) | 
| 20 | 19 | adantl 481 | . . . . . . . 8
⊢ ((𝜑 ∧ 𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin}) →
(((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) = 0 ↔ 𝑥 = (𝐼 × {0}))) | 
| 21 | 20 | necon3abid 2977 | . . . . . . 7
⊢ ((𝜑 ∧ 𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin}) →
(((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ≠ 0 ↔ ¬ 𝑥 = (𝐼 × {0}))) | 
| 22 | 18, 21 | bitr3d 281 | . . . . . 6
⊢ ((𝜑 ∧ 𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin}) → (0 <
((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) ↔ ¬ 𝑥 = (𝐼 × {0}))) | 
| 23 | 22 | imbi1d 341 | . . . . 5
⊢ ((𝜑 ∧ 𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin}) → ((0
< ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) → (𝐹‘𝑥) = (0g‘𝑅)) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅)))) | 
| 24 |  | eqeq2 2749 | . . . . . . . 8
⊢ ((𝐹‘(𝐼 × {0})) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)) → ((𝐹‘𝑥) = (𝐹‘(𝐼 × {0})) ↔ (𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)))) | 
| 25 | 24 | bibi1d 343 | . . . . . . 7
⊢ ((𝐹‘(𝐼 × {0})) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)) → (((𝐹‘𝑥) = (𝐹‘(𝐼 × {0})) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅))) ↔ ((𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅))))) | 
| 26 |  | eqeq2 2749 | . . . . . . . 8
⊢
((0g‘𝑅) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)) → ((𝐹‘𝑥) = (0g‘𝑅) ↔ (𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)))) | 
| 27 | 26 | bibi1d 343 | . . . . . . 7
⊢
((0g‘𝑅) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)) → (((𝐹‘𝑥) = (0g‘𝑅) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅))) ↔ ((𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅))))) | 
| 28 |  | fveq2 6906 | . . . . . . . . 9
⊢ (𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (𝐹‘(𝐼 × {0}))) | 
| 29 |  | pm2.24 124 | . . . . . . . . 9
⊢ (𝑥 = (𝐼 × {0}) → (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅))) | 
| 30 | 28, 29 | 2thd 265 | . . . . . . . 8
⊢ (𝑥 = (𝐼 × {0}) → ((𝐹‘𝑥) = (𝐹‘(𝐼 × {0})) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅)))) | 
| 31 | 30 | adantl 481 | . . . . . . 7
⊢ ((𝜑 ∧ 𝑥 = (𝐼 × {0})) → ((𝐹‘𝑥) = (𝐹‘(𝐼 × {0})) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅)))) | 
| 32 |  | biimt 360 | . . . . . . . 8
⊢ (¬
𝑥 = (𝐼 × {0}) → ((𝐹‘𝑥) = (0g‘𝑅) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅)))) | 
| 33 | 32 | adantl 481 | . . . . . . 7
⊢ ((𝜑 ∧ ¬ 𝑥 = (𝐼 × {0})) → ((𝐹‘𝑥) = (0g‘𝑅) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅)))) | 
| 34 | 25, 27, 31, 33 | ifbothda 4564 | . . . . . 6
⊢ (𝜑 → ((𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅)))) | 
| 35 | 34 | adantr 480 | . . . . 5
⊢ ((𝜑 ∧ 𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin}) → ((𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)) ↔ (¬ 𝑥 = (𝐼 × {0}) → (𝐹‘𝑥) = (0g‘𝑅)))) | 
| 36 | 23, 35 | bitr4d 282 | . . . 4
⊢ ((𝜑 ∧ 𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin}) → ((0
< ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) → (𝐹‘𝑥) = (0g‘𝑅)) ↔ (𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)))) | 
| 37 | 36 | ralbidva 3176 | . . 3
⊢ (𝜑 → (∀𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} (0 < ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) → (𝐹‘𝑥) = (0g‘𝑅)) ↔ ∀𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} (𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)))) | 
| 38 |  | eqid 2737 | . . . . . . 7
⊢
(Base‘𝑅) =
(Base‘𝑅) | 
| 39 | 4, 38, 5, 7, 1 | mplelf 22018 | . . . . . 6
⊢ (𝜑 → 𝐹:{𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈
Fin}⟶(Base‘𝑅)) | 
| 40 | 39 | feqmptd 6977 | . . . . 5
⊢ (𝜑 → 𝐹 = (𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦ (𝐹‘𝑥))) | 
| 41 |  | mdegle0.a | . . . . . 6
⊢ 𝐴 = (algSc‘𝑌) | 
| 42 |  | mdegaddle.i | . . . . . 6
⊢ (𝜑 → 𝐼 ∈ 𝑉) | 
| 43 |  | mdegaddle.r | . . . . . 6
⊢ (𝜑 → 𝑅 ∈ Ring) | 
| 44 | 7 | psrbag0 22086 | . . . . . . . 8
⊢ (𝐼 ∈ 𝑉 → (𝐼 × {0}) ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈
Fin}) | 
| 45 | 42, 44 | syl 17 | . . . . . . 7
⊢ (𝜑 → (𝐼 × {0}) ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈
Fin}) | 
| 46 | 39, 45 | ffvelcdmd 7105 | . . . . . 6
⊢ (𝜑 → (𝐹‘(𝐼 × {0})) ∈ (Base‘𝑅)) | 
| 47 | 4, 7, 6, 38, 41, 42, 43, 46 | mplascl 22088 | . . . . 5
⊢ (𝜑 → (𝐴‘(𝐹‘(𝐼 × {0}))) = (𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)))) | 
| 48 | 40, 47 | eqeq12d 2753 | . . . 4
⊢ (𝜑 → (𝐹 = (𝐴‘(𝐹‘(𝐼 × {0}))) ↔ (𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦ (𝐹‘𝑥)) = (𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅))))) | 
| 49 |  | fvex 6919 | . . . . . 6
⊢ (𝐹‘𝑥) ∈ V | 
| 50 | 49 | rgenw 3065 | . . . . 5
⊢
∀𝑥 ∈
{𝑎 ∈
(ℕ0 ↑m 𝐼) ∣ (◡𝑎 “ ℕ) ∈ Fin} (𝐹‘𝑥) ∈ V | 
| 51 |  | mpteqb 7035 | . . . . 5
⊢
(∀𝑥 ∈
{𝑎 ∈
(ℕ0 ↑m 𝐼) ∣ (◡𝑎 “ ℕ) ∈ Fin} (𝐹‘𝑥) ∈ V → ((𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦ (𝐹‘𝑥)) = (𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅))) ↔ ∀𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} (𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)))) | 
| 52 | 50, 51 | mp1i 13 | . . . 4
⊢ (𝜑 → ((𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦ (𝐹‘𝑥)) = (𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅))) ↔ ∀𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} (𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)))) | 
| 53 | 48, 52 | bitrd 279 | . . 3
⊢ (𝜑 → (𝐹 = (𝐴‘(𝐹‘(𝐼 × {0}))) ↔ ∀𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} (𝐹‘𝑥) = if(𝑥 = (𝐼 × {0}), (𝐹‘(𝐼 × {0})), (0g‘𝑅)))) | 
| 54 | 37, 53 | bitr4d 282 | . 2
⊢ (𝜑 → (∀𝑥 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} (0 < ((𝑏 ∈ {𝑎 ∈ (ℕ0
↑m 𝐼)
∣ (◡𝑎 “ ℕ) ∈ Fin} ↦
(ℂfld Σg 𝑏))‘𝑥) → (𝐹‘𝑥) = (0g‘𝑅)) ↔ 𝐹 = (𝐴‘(𝐹‘(𝐼 × {0}))))) | 
| 55 | 10, 54 | bitrd 279 | 1
⊢ (𝜑 → ((𝐷‘𝐹) ≤ 0 ↔ 𝐹 = (𝐴‘(𝐹‘(𝐼 × {0}))))) |