Proof of Theorem dgradd2
| Step | Hyp | Ref
| Expression |
| 1 | | plyaddcl 23976 |
. . . . . 6
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆)) → (𝐹 ∘𝑓 + 𝐺) ∈
(Poly‘ℂ)) |
| 2 | 1 | 3adant3 1081 |
. . . . 5
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (𝐹 ∘𝑓 + 𝐺) ∈
(Poly‘ℂ)) |
| 3 | | dgrcl 23989 |
. . . . 5
⊢ ((𝐹 ∘𝑓 +
𝐺) ∈
(Poly‘ℂ) → (deg‘(𝐹 ∘𝑓 + 𝐺)) ∈
ℕ0) |
| 4 | 2, 3 | syl 17 |
. . . 4
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (deg‘(𝐹 ∘𝑓 + 𝐺)) ∈
ℕ0) |
| 5 | 4 | nn0red 11352 |
. . 3
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (deg‘(𝐹 ∘𝑓 + 𝐺)) ∈
ℝ) |
| 6 | | dgradd.2 |
. . . . . . 7
⊢ 𝑁 = (deg‘𝐺) |
| 7 | | dgrcl 23989 |
. . . . . . 7
⊢ (𝐺 ∈ (Poly‘𝑆) → (deg‘𝐺) ∈
ℕ0) |
| 8 | 6, 7 | syl5eqel 2705 |
. . . . . 6
⊢ (𝐺 ∈ (Poly‘𝑆) → 𝑁 ∈
ℕ0) |
| 9 | 8 | 3ad2ant2 1083 |
. . . . 5
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝑁 ∈
ℕ0) |
| 10 | 9 | nn0red 11352 |
. . . 4
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝑁 ∈ ℝ) |
| 11 | | dgradd.1 |
. . . . . . 7
⊢ 𝑀 = (deg‘𝐹) |
| 12 | | dgrcl 23989 |
. . . . . . 7
⊢ (𝐹 ∈ (Poly‘𝑆) → (deg‘𝐹) ∈
ℕ0) |
| 13 | 11, 12 | syl5eqel 2705 |
. . . . . 6
⊢ (𝐹 ∈ (Poly‘𝑆) → 𝑀 ∈
ℕ0) |
| 14 | 13 | 3ad2ant1 1082 |
. . . . 5
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝑀 ∈
ℕ0) |
| 15 | 14 | nn0red 11352 |
. . . 4
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝑀 ∈ ℝ) |
| 16 | 10, 15 | ifcld 4131 |
. . 3
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → if(𝑀 ≤ 𝑁, 𝑁, 𝑀) ∈ ℝ) |
| 17 | 11, 6 | dgradd 24023 |
. . . 4
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆)) → (deg‘(𝐹 ∘𝑓 + 𝐺)) ≤ if(𝑀 ≤ 𝑁, 𝑁, 𝑀)) |
| 18 | 17 | 3adant3 1081 |
. . 3
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (deg‘(𝐹 ∘𝑓 + 𝐺)) ≤ if(𝑀 ≤ 𝑁, 𝑁, 𝑀)) |
| 19 | 10 | leidd 10594 |
. . . 4
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝑁 ≤ 𝑁) |
| 20 | | simp3 1063 |
. . . . 5
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝑀 < 𝑁) |
| 21 | 15, 10, 20 | ltled 10185 |
. . . 4
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝑀 ≤ 𝑁) |
| 22 | | breq1 4656 |
. . . . 5
⊢ (𝑁 = if(𝑀 ≤ 𝑁, 𝑁, 𝑀) → (𝑁 ≤ 𝑁 ↔ if(𝑀 ≤ 𝑁, 𝑁, 𝑀) ≤ 𝑁)) |
| 23 | | breq1 4656 |
. . . . 5
⊢ (𝑀 = if(𝑀 ≤ 𝑁, 𝑁, 𝑀) → (𝑀 ≤ 𝑁 ↔ if(𝑀 ≤ 𝑁, 𝑁, 𝑀) ≤ 𝑁)) |
| 24 | 22, 23 | ifboth 4124 |
. . . 4
⊢ ((𝑁 ≤ 𝑁 ∧ 𝑀 ≤ 𝑁) → if(𝑀 ≤ 𝑁, 𝑁, 𝑀) ≤ 𝑁) |
| 25 | 19, 21, 24 | syl2anc 693 |
. . 3
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → if(𝑀 ≤ 𝑁, 𝑁, 𝑀) ≤ 𝑁) |
| 26 | 5, 16, 10, 18, 25 | letrd 10194 |
. 2
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (deg‘(𝐹 ∘𝑓 + 𝐺)) ≤ 𝑁) |
| 27 | | eqid 2622 |
. . . . . . . 8
⊢
(coeff‘𝐹) =
(coeff‘𝐹) |
| 28 | | eqid 2622 |
. . . . . . . 8
⊢
(coeff‘𝐺) =
(coeff‘𝐺) |
| 29 | 27, 28 | coeadd 24007 |
. . . . . . 7
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆)) → (coeff‘(𝐹 ∘𝑓 + 𝐺)) = ((coeff‘𝐹) ∘𝑓 +
(coeff‘𝐺))) |
| 30 | 29 | 3adant3 1081 |
. . . . . 6
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (coeff‘(𝐹 ∘𝑓 + 𝐺)) = ((coeff‘𝐹) ∘𝑓 +
(coeff‘𝐺))) |
| 31 | 30 | fveq1d 6193 |
. . . . 5
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → ((coeff‘(𝐹 ∘𝑓 + 𝐺))‘𝑁) = (((coeff‘𝐹) ∘𝑓 +
(coeff‘𝐺))‘𝑁)) |
| 32 | 27 | coef3 23988 |
. . . . . . . . 9
⊢ (𝐹 ∈ (Poly‘𝑆) → (coeff‘𝐹):ℕ0⟶ℂ) |
| 33 | 32 | 3ad2ant1 1082 |
. . . . . . . 8
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (coeff‘𝐹):ℕ0⟶ℂ) |
| 34 | | ffn 6045 |
. . . . . . . 8
⊢
((coeff‘𝐹):ℕ0⟶ℂ →
(coeff‘𝐹) Fn
ℕ0) |
| 35 | 33, 34 | syl 17 |
. . . . . . 7
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (coeff‘𝐹) Fn ℕ0) |
| 36 | 28 | coef3 23988 |
. . . . . . . . 9
⊢ (𝐺 ∈ (Poly‘𝑆) → (coeff‘𝐺):ℕ0⟶ℂ) |
| 37 | 36 | 3ad2ant2 1083 |
. . . . . . . 8
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (coeff‘𝐺):ℕ0⟶ℂ) |
| 38 | | ffn 6045 |
. . . . . . . 8
⊢
((coeff‘𝐺):ℕ0⟶ℂ →
(coeff‘𝐺) Fn
ℕ0) |
| 39 | 37, 38 | syl 17 |
. . . . . . 7
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (coeff‘𝐺) Fn ℕ0) |
| 40 | | nn0ex 11298 |
. . . . . . . 8
⊢
ℕ0 ∈ V |
| 41 | 40 | a1i 11 |
. . . . . . 7
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → ℕ0 ∈
V) |
| 42 | | inidm 3822 |
. . . . . . 7
⊢
(ℕ0 ∩ ℕ0) =
ℕ0 |
| 43 | 15, 10 | ltnled 10184 |
. . . . . . . . . 10
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (𝑀 < 𝑁 ↔ ¬ 𝑁 ≤ 𝑀)) |
| 44 | 20, 43 | mpbid 222 |
. . . . . . . . 9
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → ¬ 𝑁 ≤ 𝑀) |
| 45 | | simp1 1061 |
. . . . . . . . . . 11
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝐹 ∈ (Poly‘𝑆)) |
| 46 | 27, 11 | dgrub 23990 |
. . . . . . . . . . . 12
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝑁 ∈ ℕ0 ∧
((coeff‘𝐹)‘𝑁) ≠ 0) → 𝑁 ≤ 𝑀) |
| 47 | 46 | 3expia 1267 |
. . . . . . . . . . 11
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝑁 ∈ ℕ0) →
(((coeff‘𝐹)‘𝑁) ≠ 0 → 𝑁 ≤ 𝑀)) |
| 48 | 45, 9, 47 | syl2anc 693 |
. . . . . . . . . 10
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (((coeff‘𝐹)‘𝑁) ≠ 0 → 𝑁 ≤ 𝑀)) |
| 49 | 48 | necon1bd 2812 |
. . . . . . . . 9
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (¬ 𝑁 ≤ 𝑀 → ((coeff‘𝐹)‘𝑁) = 0)) |
| 50 | 44, 49 | mpd 15 |
. . . . . . . 8
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → ((coeff‘𝐹)‘𝑁) = 0) |
| 51 | 50 | adantr 481 |
. . . . . . 7
⊢ (((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) ∧ 𝑁 ∈ ℕ0) →
((coeff‘𝐹)‘𝑁) = 0) |
| 52 | | eqidd 2623 |
. . . . . . 7
⊢ (((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) ∧ 𝑁 ∈ ℕ0) →
((coeff‘𝐺)‘𝑁) = ((coeff‘𝐺)‘𝑁)) |
| 53 | 35, 39, 41, 41, 42, 51, 52 | ofval 6906 |
. . . . . 6
⊢ (((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) ∧ 𝑁 ∈ ℕ0) →
(((coeff‘𝐹)
∘𝑓 + (coeff‘𝐺))‘𝑁) = (0 + ((coeff‘𝐺)‘𝑁))) |
| 54 | 9, 53 | mpdan 702 |
. . . . 5
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (((coeff‘𝐹) ∘𝑓 +
(coeff‘𝐺))‘𝑁) = (0 + ((coeff‘𝐺)‘𝑁))) |
| 55 | 37, 9 | ffvelrnd 6360 |
. . . . . 6
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → ((coeff‘𝐺)‘𝑁) ∈ ℂ) |
| 56 | 55 | addid2d 10237 |
. . . . 5
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (0 + ((coeff‘𝐺)‘𝑁)) = ((coeff‘𝐺)‘𝑁)) |
| 57 | 31, 54, 56 | 3eqtrd 2660 |
. . . 4
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → ((coeff‘(𝐹 ∘𝑓 + 𝐺))‘𝑁) = ((coeff‘𝐺)‘𝑁)) |
| 58 | | simp2 1062 |
. . . . 5
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝐺 ∈ (Poly‘𝑆)) |
| 59 | | 0red 10041 |
. . . . . . 7
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 0 ∈ ℝ) |
| 60 | 14 | nn0ge0d 11354 |
. . . . . . 7
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 0 ≤ 𝑀) |
| 61 | 59, 15, 10, 60, 20 | lelttrd 10195 |
. . . . . 6
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 0 < 𝑁) |
| 62 | 61 | gt0ne0d 10592 |
. . . . 5
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝑁 ≠ 0) |
| 63 | 6, 28 | dgreq0 24021 |
. . . . . . 7
⊢ (𝐺 ∈ (Poly‘𝑆) → (𝐺 = 0𝑝 ↔
((coeff‘𝐺)‘𝑁) = 0)) |
| 64 | | fveq2 6191 |
. . . . . . . 8
⊢ (𝐺 = 0𝑝 →
(deg‘𝐺) =
(deg‘0𝑝)) |
| 65 | | dgr0 24018 |
. . . . . . . . 9
⊢
(deg‘0𝑝) = 0 |
| 66 | 65 | eqcomi 2631 |
. . . . . . . 8
⊢ 0 =
(deg‘0𝑝) |
| 67 | 64, 6, 66 | 3eqtr4g 2681 |
. . . . . . 7
⊢ (𝐺 = 0𝑝 →
𝑁 = 0) |
| 68 | 63, 67 | syl6bir 244 |
. . . . . 6
⊢ (𝐺 ∈ (Poly‘𝑆) → (((coeff‘𝐺)‘𝑁) = 0 → 𝑁 = 0)) |
| 69 | 68 | necon3d 2815 |
. . . . 5
⊢ (𝐺 ∈ (Poly‘𝑆) → (𝑁 ≠ 0 → ((coeff‘𝐺)‘𝑁) ≠ 0)) |
| 70 | 58, 62, 69 | sylc 65 |
. . . 4
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → ((coeff‘𝐺)‘𝑁) ≠ 0) |
| 71 | 57, 70 | eqnetrd 2861 |
. . 3
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → ((coeff‘(𝐹 ∘𝑓 + 𝐺))‘𝑁) ≠ 0) |
| 72 | | eqid 2622 |
. . . 4
⊢
(coeff‘(𝐹
∘𝑓 + 𝐺)) = (coeff‘(𝐹 ∘𝑓 + 𝐺)) |
| 73 | | eqid 2622 |
. . . 4
⊢
(deg‘(𝐹
∘𝑓 + 𝐺)) = (deg‘(𝐹 ∘𝑓 + 𝐺)) |
| 74 | 72, 73 | dgrub 23990 |
. . 3
⊢ (((𝐹 ∘𝑓 +
𝐺) ∈
(Poly‘ℂ) ∧ 𝑁 ∈ ℕ0 ∧
((coeff‘(𝐹
∘𝑓 + 𝐺))‘𝑁) ≠ 0) → 𝑁 ≤ (deg‘(𝐹 ∘𝑓 + 𝐺))) |
| 75 | 2, 9, 71, 74 | syl3anc 1326 |
. 2
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → 𝑁 ≤ (deg‘(𝐹 ∘𝑓 + 𝐺))) |
| 76 | 5, 10 | letri3d 10179 |
. 2
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → ((deg‘(𝐹 ∘𝑓 + 𝐺)) = 𝑁 ↔ ((deg‘(𝐹 ∘𝑓 + 𝐺)) ≤ 𝑁 ∧ 𝑁 ≤ (deg‘(𝐹 ∘𝑓 + 𝐺))))) |
| 77 | 26, 75, 76 | mpbir2and 957 |
1
⊢ ((𝐹 ∈ (Poly‘𝑆) ∧ 𝐺 ∈ (Poly‘𝑆) ∧ 𝑀 < 𝑁) → (deg‘(𝐹 ∘𝑓 + 𝐺)) = 𝑁) |