Metamath Proof Explorer


Definition df-tayl

Description: Define the Taylor polynomial or Taylor series of a function. TODO-AV: n e. ( NN0 u. { +oo } ) should be replaced by n e. NN0* . (Contributed by Mario Carneiro, 30-Dec-2016)

Ref Expression
Assertion df-tayl Tayl = ( 𝑠 ∈ { ℝ , ℂ } , 𝑓 ∈ ( ℂ ↑pm 𝑠 ) ↦ ( 𝑛 ∈ ( ℕ0 ∪ { +∞ } ) , 𝑎 ∈ ∩ 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) dom ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ↦ ∪ 𝑥 ∈ ℂ ( { 𝑥 } × ( ℂfld tsums ( 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) ↦ ( ( ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 ) / ( ! ‘ 𝑘 ) ) · ( ( 𝑥 − 𝑎 ) ↑ 𝑘 ) ) ) ) ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 ctayl ⊢ Tayl
1 vs ⊢ 𝑠
2 cr ⊢ ℝ
3 cc ⊢ ℂ
4 2 3 cpr ⊢ { ℝ , ℂ }
5 vf ⊢ 𝑓
6 cpm ⊢ ↑pm
7 1 cv ⊢ 𝑠
8 3 7 6 co ⊢ ( ℂ ↑pm 𝑠 )
9 vn ⊢ 𝑛
10 cn0 ⊢ ℕ0
11 cpnf ⊢ +∞
12 11 csn ⊢ { +∞ }
13 10 12 cun ⊢ ( ℕ0 ∪ { +∞ } )
14 va ⊢ 𝑎
15 vk ⊢ 𝑘
16 cc0 ⊢ 0
17 cicc ⊢ [,]
18 9 cv ⊢ 𝑛
19 16 18 17 co ⊢ ( 0 [,] 𝑛 )
20 cz ⊢ ℤ
21 19 20 cin ⊢ ( ( 0 [,] 𝑛 ) ∩ ℤ )
22 cdvn ⊢ D𝑛
23 5 cv ⊢ 𝑓
24 7 23 22 co ⊢ ( 𝑠 D𝑛 𝑓 )
25 15 cv ⊢ 𝑘
26 25 24 cfv ⊢ ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 )
27 26 cdm ⊢ dom ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 )
28 15 21 27 ciin ⊢ ∩ 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) dom ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 )
29 vx ⊢ 𝑥
30 29 cv ⊢ 𝑥
31 30 csn ⊢ { 𝑥 }
32 ccnfld ⊢ ℂfld
33 ctsu ⊢ tsums
34 14 cv ⊢ 𝑎
35 34 26 cfv ⊢ ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 )
36 cdiv ⊢ /
37 cfa ⊢ !
38 25 37 cfv ⊢ ( ! ‘ 𝑘 )
39 35 38 36 co ⊢ ( ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 ) / ( ! ‘ 𝑘 ) )
40 cmul ⊢ ·
41 cmin ⊢ −
42 30 34 41 co ⊢ ( 𝑥 − 𝑎 )
43 cexp ⊢ ↑
44 42 25 43 co ⊢ ( ( 𝑥 − 𝑎 ) ↑ 𝑘 )
45 39 44 40 co ⊢ ( ( ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 ) / ( ! ‘ 𝑘 ) ) · ( ( 𝑥 − 𝑎 ) ↑ 𝑘 ) )
46 15 21 45 cmpt ⊢ ( 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) ↦ ( ( ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 ) / ( ! ‘ 𝑘 ) ) · ( ( 𝑥 − 𝑎 ) ↑ 𝑘 ) ) )
47 32 46 33 co ⊢ ( ℂfld tsums ( 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) ↦ ( ( ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 ) / ( ! ‘ 𝑘 ) ) · ( ( 𝑥 − 𝑎 ) ↑ 𝑘 ) ) ) )
48 31 47 cxp ⊢ ( { 𝑥 } × ( ℂfld tsums ( 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) ↦ ( ( ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 ) / ( ! ‘ 𝑘 ) ) · ( ( 𝑥 − 𝑎 ) ↑ 𝑘 ) ) ) ) )
49 29 3 48 ciun ⊢ ∪ 𝑥 ∈ ℂ ( { 𝑥 } × ( ℂfld tsums ( 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) ↦ ( ( ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 ) / ( ! ‘ 𝑘 ) ) · ( ( 𝑥 − 𝑎 ) ↑ 𝑘 ) ) ) ) )
50 9 14 13 28 49 cmpo ⊢ ( 𝑛 ∈ ( ℕ0 ∪ { +∞ } ) , 𝑎 ∈ ∩ 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) dom ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ↦ ∪ 𝑥 ∈ ℂ ( { 𝑥 } × ( ℂfld tsums ( 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) ↦ ( ( ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 ) / ( ! ‘ 𝑘 ) ) · ( ( 𝑥 − 𝑎 ) ↑ 𝑘 ) ) ) ) ) )
51 1 5 4 8 50 cmpo ⊢ ( 𝑠 ∈ { ℝ , ℂ } , 𝑓 ∈ ( ℂ ↑pm 𝑠 ) ↦ ( 𝑛 ∈ ( ℕ0 ∪ { +∞ } ) , 𝑎 ∈ ∩ 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) dom ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ↦ ∪ 𝑥 ∈ ℂ ( { 𝑥 } × ( ℂfld tsums ( 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) ↦ ( ( ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 ) / ( ! ‘ 𝑘 ) ) · ( ( 𝑥 − 𝑎 ) ↑ 𝑘 ) ) ) ) ) ) )
52 0 51 wceq ⊢ Tayl = ( 𝑠 ∈ { ℝ , ℂ } , 𝑓 ∈ ( ℂ ↑pm 𝑠 ) ↦ ( 𝑛 ∈ ( ℕ0 ∪ { +∞ } ) , 𝑎 ∈ ∩ 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) dom ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ↦ ∪ 𝑥 ∈ ℂ ( { 𝑥 } × ( ℂfld tsums ( 𝑘 ∈ ( ( 0 [,] 𝑛 ) ∩ ℤ ) ↦ ( ( ( ( ( 𝑠 D𝑛 𝑓 ) ‘ 𝑘 ) ‘ 𝑎 ) / ( ! ‘ 𝑘 ) ) · ( ( 𝑥 − 𝑎 ) ↑ 𝑘 ) ) ) ) ) ) )