Metamath Proof Explorer


Theorem dvcn

Description: A differentiable function is continuous. (Contributed by Mario Carneiro, 7-Sep-2014) (Revised by Mario Carneiro, 7-Sep-2015)

Ref Expression
Assertion dvcn ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → F : A ⟶cn ℂ

Proof

Step Hyp Ref Expression
1 simpl2 ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → F : A ⟶ ℂ
2 eqid ⊢ TopOpen ⁡ ℂ fld ↾ 𝑡 A = TopOpen ⁡ ℂ fld ↾ 𝑡 A
3 eqid ⊢ TopOpen ⁡ ℂ fld = TopOpen ⁡ ℂ fld
4 2 3 dvcnp2 ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ x ∈ dom ⁡ F S ′ → F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A CnP TopOpen ⁡ ℂ fld ⁡ x
5 4 ralrimiva ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S → ∀ x ∈ dom ⁡ F S ′ F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A CnP TopOpen ⁡ ℂ fld ⁡ x
6 raleq ⊢ dom ⁡ F S ′ = A → ∀ x ∈ dom ⁡ F S ′ F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A CnP TopOpen ⁡ ℂ fld ⁡ x ↔ ∀ x ∈ A F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A CnP TopOpen ⁡ ℂ fld ⁡ x
7 6 biimpd ⊢ dom ⁡ F S ′ = A → ∀ x ∈ dom ⁡ F S ′ F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A CnP TopOpen ⁡ ℂ fld ⁡ x → ∀ x ∈ A F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A CnP TopOpen ⁡ ℂ fld ⁡ x
8 5 7 mpan9 ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → ∀ x ∈ A F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A CnP TopOpen ⁡ ℂ fld ⁡ x
9 3 cnfldtopon ⊢ TopOpen ⁡ ℂ fld ∈ TopOn ⁡ ℂ
10 simpl3 ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → A ⊆ S
11 simpl1 ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → S ⊆ ℂ
12 10 11 sstrd ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → A ⊆ ℂ
13 resttopon ⊢ TopOpen ⁡ ℂ fld ∈ TopOn ⁡ ℂ ∧ A ⊆ ℂ → TopOpen ⁡ ℂ fld ↾ 𝑡 A ∈ TopOn ⁡ A
14 9 12 13 sylancr ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → TopOpen ⁡ ℂ fld ↾ 𝑡 A ∈ TopOn ⁡ A
15 cncnp ⊢ TopOpen ⁡ ℂ fld ↾ 𝑡 A ∈ TopOn ⁡ A ∧ TopOpen ⁡ ℂ fld ∈ TopOn ⁡ ℂ → F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A Cn TopOpen ⁡ ℂ fld ↔ F : A ⟶ ℂ ∧ ∀ x ∈ A F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A CnP TopOpen ⁡ ℂ fld ⁡ x
16 14 9 15 sylancl ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A Cn TopOpen ⁡ ℂ fld ↔ F : A ⟶ ℂ ∧ ∀ x ∈ A F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A CnP TopOpen ⁡ ℂ fld ⁡ x
17 1 8 16 mpbir2and ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → F ∈ TopOpen ⁡ ℂ fld ↾ 𝑡 A Cn TopOpen ⁡ ℂ fld
18 ssid ⊢ ℂ ⊆ ℂ
19 9 toponrestid ⊢ TopOpen ⁡ ℂ fld = TopOpen ⁡ ℂ fld ↾ 𝑡 ℂ
20 3 2 19 cncfcn ⊢ A ⊆ ℂ ∧ ℂ ⊆ ℂ → A ⟶cn ℂ = TopOpen ⁡ ℂ fld ↾ 𝑡 A Cn TopOpen ⁡ ℂ fld
21 12 18 20 sylancl ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → A ⟶cn ℂ = TopOpen ⁡ ℂ fld ↾ 𝑡 A Cn TopOpen ⁡ ℂ fld
22 17 21 eleqtrrd ⊢ S ⊆ ℂ ∧ F : A ⟶ ℂ ∧ A ⊆ S ∧ dom ⁡ F S ′ = A → F : A ⟶cn ℂ