refine Filter.Tendsto.sub ?_ ?_
F : Type u_1
inst✝² : NormedAddCommGroup F
inst✝¹ : NormedSpace ℂ F
inst✝ : CompleteSpace F
f : 𝓢(ℝ, F)
ξ : ℝ
h_cover : AECover volume Filter.atTop fun i => Set.Ioc (-↑i) ↑i
⊢ Filter.Tendsto
    (fun x =>
      ((hasTemperateGrowth_smul
              (_ : Function.HasTemperateGrowth fun x => ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ))))))
            f)
          x -
        ((hasTemperateGrowth_smul
              (_ : Function.HasTemperateGrowth fun x => ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ))))))
            f)
          (-x))
    Filter.atTop (nhds (0 - 0))
case refine_1
F : Type u_1
inst✝² : NormedAddCommGroup F
inst✝¹ : NormedSpace ℂ F
inst✝ : CompleteSpace F
f : 𝓢(ℝ, F)
ξ : ℝ
h_cover : AECover volume Filter.atTop fun i => Set.Ioc (-↑i) ↑i
⊢ Filter.Tendsto
    (fun x =>
      ((hasTemperateGrowth_smul
            (_ : Function.HasTemperateGrowth fun x => ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ))))))
          f)
        x)
    Filter.atTop (nhds 0)

case refine_2
F : Type u_1
inst✝² : NormedAddCommGroup F
inst✝¹ : NormedSpace ℂ F
inst✝ : CompleteSpace F
f : 𝓢(ℝ, F)
ξ : ℝ
h_cover : AECover volume Filter.atTop fun i => Set.Ioc (-↑i) ↑i
⊢ Filter.Tendsto
    (fun x =>
      ((hasTemperateGrowth_smul
            (_ : Function.HasTemperateGrowth fun x => ↑(Real.fourierChar (Multiplicative.ofAdd (-(x * ξ))))))
          f)
        (-x))
    Filter.atTop (nhds 0)