Metamath Proof Explorer


Theorem bj-inftyexpitaudisj

Description: An element of the circle at infinity is not a complex number. (Contributed by BJ, 4-Feb-2023)

Ref Expression
Assertion bj-inftyexpitaudisj ⊢ ¬ +∞e iτ ⁡ A ∈ ℂ

Proof

Step Hyp Ref Expression
1 2fveq3 ⊢ x = A → { R ⁡ 1 st ⁡ x = { R ⁡ 1 st ⁡ A
2 1 opeq1d ⊢ x = A → { R ⁡ 1 st ⁡ x 𝑹 = { R ⁡ 1 st ⁡ A 𝑹
3 df-bj-inftyexpitau ⊢ +∞e iτ = x ∈ ℝ ⟼ { R ⁡ 1 st ⁡ x 𝑹
4 opex ⊢ { R ⁡ 1 st ⁡ A 𝑹 ∈ V
5 2 3 4 fvmpt ⊢ A ∈ ℝ → +∞e iτ ⁡ A = { R ⁡ 1 st ⁡ A 𝑹
6 opex ⊢ { R ⁡ 1 st ⁡ y 𝑹 ∈ V
7 df-bj-inftyexpitau ⊢ +∞e iτ = y ∈ ℝ ⟼ { R ⁡ 1 st ⁡ y 𝑹
8 6 7 dmmpti ⊢ dom ⁡ +∞e iτ = ℝ
9 5 8 eleq2s ⊢ A ∈ dom ⁡ +∞e iτ → +∞e iτ ⁡ A = { R ⁡ 1 st ⁡ A 𝑹
10 nrex1 ⊢ 𝑹 ∈ V
11 bj-nsnid ⊢ 𝑹 ∈ V → ¬ 𝑹 ∈ 𝑹
12 10 11 ax-mp ⊢ ¬ 𝑹 ∈ 𝑹
13 12 intnan ⊢ ¬ { R ⁡ 1 st ⁡ A ∈ 𝑹 ∧ 𝑹 ∈ 𝑹
14 opelxp ⊢ { R ⁡ 1 st ⁡ A 𝑹 ∈ 𝑹 × 𝑹 ↔ { R ⁡ 1 st ⁡ A ∈ 𝑹 ∧ 𝑹 ∈ 𝑹
15 13 14 mtbir ⊢ ¬ { R ⁡ 1 st ⁡ A 𝑹 ∈ 𝑹 × 𝑹
16 df-c ⊢ ℂ = 𝑹 × 𝑹
17 16 eleq2i ⊢ { R ⁡ 1 st ⁡ A 𝑹 ∈ ℂ ↔ { R ⁡ 1 st ⁡ A 𝑹 ∈ 𝑹 × 𝑹
18 15 17 mtbir ⊢ ¬ { R ⁡ 1 st ⁡ A 𝑹 ∈ ℂ
19 eqcom ⊢ +∞e iτ ⁡ A = { R ⁡ 1 st ⁡ A 𝑹 ↔ { R ⁡ 1 st ⁡ A 𝑹 = +∞e iτ ⁡ A
20 19 biimpi ⊢ +∞e iτ ⁡ A = { R ⁡ 1 st ⁡ A 𝑹 → { R ⁡ 1 st ⁡ A 𝑹 = +∞e iτ ⁡ A
21 20 eleq1d ⊢ +∞e iτ ⁡ A = { R ⁡ 1 st ⁡ A 𝑹 → { R ⁡ 1 st ⁡ A 𝑹 ∈ ℂ ↔ +∞e iτ ⁡ A ∈ ℂ
22 18 21 mtbii ⊢ +∞e iτ ⁡ A = { R ⁡ 1 st ⁡ A 𝑹 → ¬ +∞e iτ ⁡ A ∈ ℂ
23 9 22 syl ⊢ A ∈ dom ⁡ +∞e iτ → ¬ +∞e iτ ⁡ A ∈ ℂ
24 0ncn ⊢ ¬ ∅ ∈ ℂ
25 ndmfv ⊢ ¬ A ∈ dom ⁡ +∞e iτ → +∞e iτ ⁡ A = ∅
26 25 eleq1d ⊢ ¬ A ∈ dom ⁡ +∞e iτ → +∞e iτ ⁡ A ∈ ℂ ↔ ∅ ∈ ℂ
27 24 26 mtbiri ⊢ ¬ A ∈ dom ⁡ +∞e iτ → ¬ +∞e iτ ⁡ A ∈ ℂ
28 23 27 pm2.61i ⊢ ¬ +∞e iτ ⁡ A ∈ ℂ