Metamath Proof Explorer


Theorem ftc1

Description: The Fundamental Theorem of Calculus, part one. The function formed by varying the right endpoint of an integral is differentiable at C with derivative F ( C ) if the original function is continuous at C . This is part of Metamath 100 proof #15. (Contributed by Mario Carneiro, 1-Sep-2014)

Ref Expression
Hypotheses ftc1.g ⊢ G = x ∈ A B ⟼ ∫ A x F ⁡ t dt
ftc1.a ⊢ φ → A ∈ ℝ
ftc1.b ⊢ φ → B ∈ ℝ
ftc1.le ⊢ φ → A ≤ B
ftc1.s ⊢ φ → A B ⊆ D
ftc1.d ⊢ φ → D ⊆ ℝ
ftc1.i ⊢ φ → F ∈ 𝐿 1
ftc1.c ⊢ φ → C ∈ A B
ftc1.f ⊢ φ → F ∈ K CnP L ⁡ C
ftc1.j ⊢ J = L ↾ 𝑡 ℝ
ftc1.k ⊢ K = L ↾ 𝑡 D
ftc1.l ⊢ L = TopOpen ⁡ ℂ fld
Assertion ftc1 ⊢ φ → C G ℝ ′ F ⁡ C

Proof

Step Hyp Ref Expression
1 ftc1.g ⊢ G = x ∈ A B ⟼ ∫ A x F ⁡ t dt
2 ftc1.a ⊢ φ → A ∈ ℝ
3 ftc1.b ⊢ φ → B ∈ ℝ
4 ftc1.le ⊢ φ → A ≤ B
5 ftc1.s ⊢ φ → A B ⊆ D
6 ftc1.d ⊢ φ → D ⊆ ℝ
7 ftc1.i ⊢ φ → F ∈ 𝐿 1
8 ftc1.c ⊢ φ → C ∈ A B
9 ftc1.f ⊢ φ → F ∈ K CnP L ⁡ C
10 ftc1.j ⊢ J = L ↾ 𝑡 ℝ
11 ftc1.k ⊢ K = L ↾ 𝑡 D
12 ftc1.l ⊢ L = TopOpen ⁡ ℂ fld
13 12 tgioo2 ⊢ topGen ⁡ ran ⁡ . = L ↾ 𝑡 ℝ
14 10 13 eqtr4i ⊢ J = topGen ⁡ ran ⁡ .
15 retop ⊢ topGen ⁡ ran ⁡ . ∈ Top
16 14 15 eqeltri ⊢ J ∈ Top
17 16 a1i ⊢ φ → J ∈ Top
18 iccssre ⊢ A ∈ ℝ ∧ B ∈ ℝ → A B ⊆ ℝ
19 2 3 18 syl2anc ⊢ φ → A B ⊆ ℝ
20 iooretop ⊢ A B ∈ topGen ⁡ ran ⁡ .
21 20 14 eleqtrri ⊢ A B ∈ J
22 21 a1i ⊢ φ → A B ∈ J
23 ioossicc ⊢ A B ⊆ A B
24 23 a1i ⊢ φ → A B ⊆ A B
25 uniretop ⊢ ℝ = ⋃ topGen ⁡ ran ⁡ .
26 14 unieqi ⊢ ⋃ J = ⋃ topGen ⁡ ran ⁡ .
27 25 26 eqtr4i ⊢ ℝ = ⋃ J
28 27 ssntr ⊢ J ∈ Top ∧ A B ⊆ ℝ ∧ A B ∈ J ∧ A B ⊆ A B → A B ⊆ int ⁡ J ⁡ A B
29 17 19 22 24 28 syl22anc ⊢ φ → A B ⊆ int ⁡ J ⁡ A B
30 29 8 sseldd ⊢ φ → C ∈ int ⁡ J ⁡ A B
31 eqid ⊢ z ∈ A B ∖ C ⟼ G ⁡ z − G ⁡ C z − C = z ∈ A B ∖ C ⟼ G ⁡ z − G ⁡ C z − C
32 1 2 3 4 5 6 7 8 9 10 11 12 31 ftc1lem6 ⊢ φ → F ⁡ C ∈ z ∈ A B ∖ C ⟼ G ⁡ z − G ⁡ C z − C lim ℂ C
33 ax-resscn ⊢ ℝ ⊆ ℂ
34 33 a1i ⊢ φ → ℝ ⊆ ℂ
35 1 2 3 4 5 6 7 8 9 10 11 12 ftc1lem3 ⊢ φ → F : D ⟶ ℂ
36 1 2 3 4 5 6 7 35 ftc1lem2 ⊢ φ → G : A B ⟶ ℂ
37 10 12 31 34 36 19 eldv ⊢ φ → C G ℝ ′ F ⁡ C ↔ C ∈ int ⁡ J ⁡ A B ∧ F ⁡ C ∈ z ∈ A B ∖ C ⟼ G ⁡ z − G ⁡ C z − C lim ℂ C
38 30 32 37 mpbir2and ⊢ φ → C G ℝ ′ F ⁡ C