rw [Complex.real_smul, smul_smul]
F : Type u_1
inst✝² : NormedAddCommGroup F
inst✝¹ : NormedSpace ℂ F
inst✝ : CompleteSpace F
f : 𝓢(ℝ, F)
ξ a b : ℝ
this :
  ∫ (x : ℝ) in a..b,
      (-ξ • (2 * ↑π * I * ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ)))))) • f x +
        ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ)))) • deriv (⇑f) x =
    ↑(Real.fourierChar (Multiplicative.ofAdd (-(b * ξ)))) • f b -
      ↑(Real.fourierChar (Multiplicative.ofAdd (-(a * ξ)))) • f a
x : ℝ
a✝ : x ∈ Set.uIcc a b
⊢ (2 * ↑π * I * ↑ξ) • ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ)))) • f x =
    (ξ • (2 * ↑π * I * ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ)))))) • f x
F : Type u_1
inst✝² : NormedAddCommGroup F
inst✝¹ : NormedSpace ℂ F
inst✝ : CompleteSpace F
f : 𝓢(ℝ, F)
ξ a b : ℝ
this :
  ∫ (x : ℝ) in a..b,
      (-ξ • (2 * ↑π * I * ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ)))))) • f x +
        ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ)))) • deriv (⇑f) x =
    ↑(Real.fourierChar (Multiplicative.ofAdd (-(b * ξ)))) • f b -
      ↑(Real.fourierChar (Multiplicative.ofAdd (-(a * ξ)))) • f a
x : ℝ
a✝ : x ∈ Set.uIcc a b
⊢ (2 * ↑π * I * ↑ξ * ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ))))) • f x =
    (↑ξ * (2 * ↑π * I * ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ)))))) • f x