Metamath Proof Explorer


Definition df-ply

Description: Define the set of polynomials on the complex numbers with coefficients in the given subset. (Contributed by Mario Carneiro, 17-Jul-2014)

Ref Expression
Assertion df-ply Poly = ( 𝑥 ∈ 𝒫 ℂ ↦ { 𝑓 ∣ ∃ 𝑛 ∈ ℕ0𝑎 ∈ ( ( 𝑥 ∪ { 0 } ) ↑m0 ) 𝑓 = ( 𝑧 ∈ ℂ ↦ Σ 𝑘 ∈ ( 0 ... 𝑛 ) ( ( 𝑎𝑘 ) · ( 𝑧𝑘 ) ) ) } )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cply Poly
1 vx 𝑥
2 cc
3 2 cpw 𝒫 ℂ
4 vf 𝑓
5 vn 𝑛
6 cn0 0
7 va 𝑎
8 1 cv 𝑥
9 cc0 0
10 9 csn { 0 }
11 8 10 cun ( 𝑥 ∪ { 0 } )
12 cmap m
13 11 6 12 co ( ( 𝑥 ∪ { 0 } ) ↑m0 )
14 4 cv 𝑓
15 vz 𝑧
16 vk 𝑘
17 cfz ...
18 5 cv 𝑛
19 9 18 17 co ( 0 ... 𝑛 )
20 7 cv 𝑎
21 16 cv 𝑘
22 21 20 cfv ( 𝑎𝑘 )
23 cmul ·
24 15 cv 𝑧
25 cexp
26 24 21 25 co ( 𝑧𝑘 )
27 22 26 23 co ( ( 𝑎𝑘 ) · ( 𝑧𝑘 ) )
28 19 27 16 csu Σ 𝑘 ∈ ( 0 ... 𝑛 ) ( ( 𝑎𝑘 ) · ( 𝑧𝑘 ) )
29 15 2 28 cmpt ( 𝑧 ∈ ℂ ↦ Σ 𝑘 ∈ ( 0 ... 𝑛 ) ( ( 𝑎𝑘 ) · ( 𝑧𝑘 ) ) )
30 14 29 wceq 𝑓 = ( 𝑧 ∈ ℂ ↦ Σ 𝑘 ∈ ( 0 ... 𝑛 ) ( ( 𝑎𝑘 ) · ( 𝑧𝑘 ) ) )
31 30 7 13 wrex 𝑎 ∈ ( ( 𝑥 ∪ { 0 } ) ↑m0 ) 𝑓 = ( 𝑧 ∈ ℂ ↦ Σ 𝑘 ∈ ( 0 ... 𝑛 ) ( ( 𝑎𝑘 ) · ( 𝑧𝑘 ) ) )
32 31 5 6 wrex 𝑛 ∈ ℕ0𝑎 ∈ ( ( 𝑥 ∪ { 0 } ) ↑m0 ) 𝑓 = ( 𝑧 ∈ ℂ ↦ Σ 𝑘 ∈ ( 0 ... 𝑛 ) ( ( 𝑎𝑘 ) · ( 𝑧𝑘 ) ) )
33 32 4 cab { 𝑓 ∣ ∃ 𝑛 ∈ ℕ0𝑎 ∈ ( ( 𝑥 ∪ { 0 } ) ↑m0 ) 𝑓 = ( 𝑧 ∈ ℂ ↦ Σ 𝑘 ∈ ( 0 ... 𝑛 ) ( ( 𝑎𝑘 ) · ( 𝑧𝑘 ) ) ) }
34 1 3 33 cmpt ( 𝑥 ∈ 𝒫 ℂ ↦ { 𝑓 ∣ ∃ 𝑛 ∈ ℕ0𝑎 ∈ ( ( 𝑥 ∪ { 0 } ) ↑m0 ) 𝑓 = ( 𝑧 ∈ ℂ ↦ Σ 𝑘 ∈ ( 0 ... 𝑛 ) ( ( 𝑎𝑘 ) · ( 𝑧𝑘 ) ) ) } )
35 0 34 wceq Poly = ( 𝑥 ∈ 𝒫 ℂ ↦ { 𝑓 ∣ ∃ 𝑛 ∈ ℕ0𝑎 ∈ ( ( 𝑥 ∪ { 0 } ) ↑m0 ) 𝑓 = ( 𝑧 ∈ ℂ ↦ Σ 𝑘 ∈ ( 0 ... 𝑛 ) ( ( 𝑎𝑘 ) · ( 𝑧𝑘 ) ) ) } )