| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ftc2ditg.x | ⊢ ( 𝜑  →  𝑋  ∈  ℝ ) | 
						
							| 2 |  | ftc2ditg.y | ⊢ ( 𝜑  →  𝑌  ∈  ℝ ) | 
						
							| 3 |  | ftc2ditg.a | ⊢ ( 𝜑  →  𝐴  ∈  ( 𝑋 [,] 𝑌 ) ) | 
						
							| 4 |  | ftc2ditg.b | ⊢ ( 𝜑  →  𝐵  ∈  ( 𝑋 [,] 𝑌 ) ) | 
						
							| 5 |  | ftc2ditg.c | ⊢ ( 𝜑  →  ( ℝ  D  𝐹 )  ∈  ( ( 𝑋 (,) 𝑌 ) –cn→ ℂ ) ) | 
						
							| 6 |  | ftc2ditg.i | ⊢ ( 𝜑  →  ( ℝ  D  𝐹 )  ∈  𝐿1 ) | 
						
							| 7 |  | ftc2ditg.f | ⊢ ( 𝜑  →  𝐹  ∈  ( ( 𝑋 [,] 𝑌 ) –cn→ ℂ ) ) | 
						
							| 8 |  | iccssre | ⊢ ( ( 𝑋  ∈  ℝ  ∧  𝑌  ∈  ℝ )  →  ( 𝑋 [,] 𝑌 )  ⊆  ℝ ) | 
						
							| 9 | 1 2 8 | syl2anc | ⊢ ( 𝜑  →  ( 𝑋 [,] 𝑌 )  ⊆  ℝ ) | 
						
							| 10 | 9 3 | sseldd | ⊢ ( 𝜑  →  𝐴  ∈  ℝ ) | 
						
							| 11 | 9 4 | sseldd | ⊢ ( 𝜑  →  𝐵  ∈  ℝ ) | 
						
							| 12 | 1 2 3 4 5 6 7 | ftc2ditglem | ⊢ ( ( 𝜑  ∧  𝐴  ≤  𝐵 )  →  ⨜ [ 𝐴  →  𝐵 ] ( ( ℝ  D  𝐹 ) ‘ 𝑡 )  d 𝑡  =  ( ( 𝐹 ‘ 𝐵 )  −  ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 13 |  | fvexd | ⊢ ( ( 𝜑  ∧  𝑡  ∈  ( 𝑋 (,) 𝑌 ) )  →  ( ( ℝ  D  𝐹 ) ‘ 𝑡 )  ∈  V ) | 
						
							| 14 |  | cncff | ⊢ ( ( ℝ  D  𝐹 )  ∈  ( ( 𝑋 (,) 𝑌 ) –cn→ ℂ )  →  ( ℝ  D  𝐹 ) : ( 𝑋 (,) 𝑌 ) ⟶ ℂ ) | 
						
							| 15 | 5 14 | syl | ⊢ ( 𝜑  →  ( ℝ  D  𝐹 ) : ( 𝑋 (,) 𝑌 ) ⟶ ℂ ) | 
						
							| 16 | 15 | feqmptd | ⊢ ( 𝜑  →  ( ℝ  D  𝐹 )  =  ( 𝑡  ∈  ( 𝑋 (,) 𝑌 )  ↦  ( ( ℝ  D  𝐹 ) ‘ 𝑡 ) ) ) | 
						
							| 17 | 16 6 | eqeltrrd | ⊢ ( 𝜑  →  ( 𝑡  ∈  ( 𝑋 (,) 𝑌 )  ↦  ( ( ℝ  D  𝐹 ) ‘ 𝑡 ) )  ∈  𝐿1 ) | 
						
							| 18 | 1 2 4 3 13 17 | ditgswap | ⊢ ( 𝜑  →  ⨜ [ 𝐴  →  𝐵 ] ( ( ℝ  D  𝐹 ) ‘ 𝑡 )  d 𝑡  =  - ⨜ [ 𝐵  →  𝐴 ] ( ( ℝ  D  𝐹 ) ‘ 𝑡 )  d 𝑡 ) | 
						
							| 19 | 18 | adantr | ⊢ ( ( 𝜑  ∧  𝐵  ≤  𝐴 )  →  ⨜ [ 𝐴  →  𝐵 ] ( ( ℝ  D  𝐹 ) ‘ 𝑡 )  d 𝑡  =  - ⨜ [ 𝐵  →  𝐴 ] ( ( ℝ  D  𝐹 ) ‘ 𝑡 )  d 𝑡 ) | 
						
							| 20 | 1 2 4 3 5 6 7 | ftc2ditglem | ⊢ ( ( 𝜑  ∧  𝐵  ≤  𝐴 )  →  ⨜ [ 𝐵  →  𝐴 ] ( ( ℝ  D  𝐹 ) ‘ 𝑡 )  d 𝑡  =  ( ( 𝐹 ‘ 𝐴 )  −  ( 𝐹 ‘ 𝐵 ) ) ) | 
						
							| 21 | 20 | negeqd | ⊢ ( ( 𝜑  ∧  𝐵  ≤  𝐴 )  →  - ⨜ [ 𝐵  →  𝐴 ] ( ( ℝ  D  𝐹 ) ‘ 𝑡 )  d 𝑡  =  - ( ( 𝐹 ‘ 𝐴 )  −  ( 𝐹 ‘ 𝐵 ) ) ) | 
						
							| 22 |  | cncff | ⊢ ( 𝐹  ∈  ( ( 𝑋 [,] 𝑌 ) –cn→ ℂ )  →  𝐹 : ( 𝑋 [,] 𝑌 ) ⟶ ℂ ) | 
						
							| 23 | 7 22 | syl | ⊢ ( 𝜑  →  𝐹 : ( 𝑋 [,] 𝑌 ) ⟶ ℂ ) | 
						
							| 24 | 23 3 | ffvelcdmd | ⊢ ( 𝜑  →  ( 𝐹 ‘ 𝐴 )  ∈  ℂ ) | 
						
							| 25 | 23 4 | ffvelcdmd | ⊢ ( 𝜑  →  ( 𝐹 ‘ 𝐵 )  ∈  ℂ ) | 
						
							| 26 | 24 25 | negsubdi2d | ⊢ ( 𝜑  →  - ( ( 𝐹 ‘ 𝐴 )  −  ( 𝐹 ‘ 𝐵 ) )  =  ( ( 𝐹 ‘ 𝐵 )  −  ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 27 | 26 | adantr | ⊢ ( ( 𝜑  ∧  𝐵  ≤  𝐴 )  →  - ( ( 𝐹 ‘ 𝐴 )  −  ( 𝐹 ‘ 𝐵 ) )  =  ( ( 𝐹 ‘ 𝐵 )  −  ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 28 | 19 21 27 | 3eqtrd | ⊢ ( ( 𝜑  ∧  𝐵  ≤  𝐴 )  →  ⨜ [ 𝐴  →  𝐵 ] ( ( ℝ  D  𝐹 ) ‘ 𝑡 )  d 𝑡  =  ( ( 𝐹 ‘ 𝐵 )  −  ( 𝐹 ‘ 𝐴 ) ) ) | 
						
							| 29 | 10 11 12 28 | lecasei | ⊢ ( 𝜑  →  ⨜ [ 𝐴  →  𝐵 ] ( ( ℝ  D  𝐹 ) ‘ 𝑡 )  d 𝑡  =  ( ( 𝐹 ‘ 𝐵 )  −  ( 𝐹 ‘ 𝐴 ) ) ) |