-- Mathlib/Analysis/Calculus/BumpFunction/Normed.lean
theorem tendsto_support_normed_smallSets {ι} {φ : ι → ContDiffBump c} {l : Filter ι}
    (hφ : Tendsto (fun i => (φ i).rOut) l (𝓝 0)) :
    Tendsto (fun i => Function.support fun x => (φ i).normed μ x) l (𝓝 c).smallSets

Proof state:
E : Type u_1
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : HasContDiffBump E
inst✝⁴ : MeasurableSpace E
c : E
μ : Measure E
inst✝³ : BorelSpace E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : IsLocallyFiniteMeasure μ
inst✝ : μ.IsOpenPosMeasure
ι : Type u_2
φ : ι → ContDiffBump c
l : Filter ι
hφ : ∀ ε > 0, ∀ᶠ (x : ι) in l, (φ x).rOut < ε
⊢ Tendsto (fun i => support fun x => (φ i).normed μ x) l (𝓝 c).smallSets

Tactic:
rw [nhds_basis_ball.smallSets.tendsto_right_iff]

Result:
E : Type u_1
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : HasContDiffBump E
inst✝⁴ : MeasurableSpace E
c : E
μ : Measure E
inst✝³ : BorelSpace E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : IsLocallyFiniteMeasure μ
inst✝ : μ.IsOpenPosMeasure
ι : Type u_2
φ : ι → ContDiffBump c
l : Filter ι
hφ : ∀ ε > 0, ∀ᶠ (x : ι) in l, (φ x).rOut < ε
⊢ ∀ (i : ℝ), 0 < i → ∀ᶠ (x : ι) in l, (support fun x_1 => (φ x).normed μ x_1) ∈ 𝒫 ball c i

Proof state:
E : Type u_1
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : HasContDiffBump E
inst✝⁴ : MeasurableSpace E
c : E
μ : Measure E
inst✝³ : BorelSpace E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : IsLocallyFiniteMeasure μ
inst✝ : μ.IsOpenPosMeasure
ι : Type u_2
φ : ι → ContDiffBump c
l : Filter ι
hφ : ∀ ε > 0, ∀ᶠ (x : ι) in l, (φ x).rOut < ε
ε : ℝ
hε : 0 < ε
i : ι
hi : (φ i).rOut < ε
⊢ ball c (φ i).rOut ∈ 𝒫 ball c ε

Tactic:
exact ball_subset_ball hi.le

Result:
no goals

Proof state:
E : Type u_1
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : HasContDiffBump E
inst✝⁴ : MeasurableSpace E
c : E
μ : Measure E
inst✝³ : BorelSpace E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : IsLocallyFiniteMeasure μ
inst✝ : μ.IsOpenPosMeasure
ι : Type u_2
φ : ι → ContDiffBump c
l : Filter ι
hφ : Tendsto (fun i => (φ i).rOut) l (𝓝 0)
⊢ Tendsto (fun i => support fun x => (φ i).normed μ x) l (𝓝 c).smallSets

Tactic:
simp_rw [NormedAddCommGroup.tendsto_nhds_zero, Real.norm_eq_abs,
  abs_eq_self.mpr (φ _).rOut_pos.le] at hφ

Result:
E : Type u_1
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : HasContDiffBump E
inst✝⁴ : MeasurableSpace E
c : E
μ : Measure E
inst✝³ : BorelSpace E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : IsLocallyFiniteMeasure μ
inst✝ : μ.IsOpenPosMeasure
ι : Type u_2
φ : ι → ContDiffBump c
l : Filter ι
hφ : ∀ ε > 0, ∀ᶠ (x : ι) in l, (φ x).rOut < ε
⊢ Tendsto (fun i => support fun x => (φ i).normed μ x) l (𝓝 c).smallSets

Proof state:
E : Type u_1
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : HasContDiffBump E
inst✝⁴ : MeasurableSpace E
c : E
μ : Measure E
inst✝³ : BorelSpace E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : IsLocallyFiniteMeasure μ
inst✝ : μ.IsOpenPosMeasure
ι : Type u_2
φ : ι → ContDiffBump c
l : Filter ι
hφ : ∀ ε > 0, ∀ᶠ (x : ι) in l, (φ x).rOut < ε
⊢ ∀ (i : ℝ), 0 < i → ∀ᶠ (x : ι) in l, (support fun x_1 => (φ x).normed μ x_1) ∈ 𝒫 ball c i

Tactic:
refine fun ε hε ↦ (hφ ε hε).mono fun i hi ↦ ?_

Result:
E : Type u_1
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : HasContDiffBump E
inst✝⁴ : MeasurableSpace E
c : E
μ : Measure E
inst✝³ : BorelSpace E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : IsLocallyFiniteMeasure μ
inst✝ : μ.IsOpenPosMeasure
ι : Type u_2
φ : ι → ContDiffBump c
l : Filter ι
hφ : ∀ ε > 0, ∀ᶠ (x : ι) in l, (φ x).rOut < ε
ε : ℝ
hε : 0 < ε
i : ι
hi : (φ i).rOut < ε
⊢ (support fun x => (φ i).normed μ x) ∈ 𝒫 ball c ε

Proof state:
E : Type u_1
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : HasContDiffBump E
inst✝⁴ : MeasurableSpace E
c : E
μ : Measure E
inst✝³ : BorelSpace E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : IsLocallyFiniteMeasure μ
inst✝ : μ.IsOpenPosMeasure
ι : Type u_2
φ : ι → ContDiffBump c
l : Filter ι
hφ : ∀ ε > 0, ∀ᶠ (x : ι) in l, (φ x).rOut < ε
ε : ℝ
hε : 0 < ε
i : ι
hi : (φ i).rOut < ε
⊢ (support fun x => (φ i).normed μ x) ∈ 𝒫 ball c ε

Tactic:
rw [(φ i).support_normed_eq]

Result:
E : Type u_1
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : HasContDiffBump E
inst✝⁴ : MeasurableSpace E
c : E
μ : Measure E
inst✝³ : BorelSpace E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : IsLocallyFiniteMeasure μ
inst✝ : μ.IsOpenPosMeasure
ι : Type u_2
φ : ι → ContDiffBump c
l : Filter ι
hφ : ∀ ε > 0, ∀ᶠ (x : ι) in l, (φ x).rOut < ε
ε : ℝ
hε : 0 < ε
i : ι
hi : (φ i).rOut < ε
⊢ ball c (φ i).rOut ∈ 𝒫 ball c ε