use Ψ
case intro.intro.intro.intro
n : ℕ
A a b c d u x y t σ' : ℝ
ψ Ψ✝ : ℝ → ℂ
F G : ℂ → ℂ
f : ℕ → ℂ
𝕜 : Type
inst✝ : _root_.RCLike 𝕜
h1 : a < b
h3 : c < d
Ψ : ℝ → ℝ
hΨSmooth : Smooth (modelWithCornersSelf ℝ ℝ) (modelWithCornersSelf ℝ ℝ) Ψ
hΨrange : range Ψ ⊆ Icc 0 1
hΨ0 : ∀ (x : ℝ), x ≤ a ∨ d ≤ x ↔ Ψ x = 0
hΨ1 : ∀ (x : ℝ), b ≤ x ∧ x ≤ c ↔ Ψ x = 1
⊢ ∃ Ψ,
    ContDiff ℝ ⊤ Ψ ∧
      HasCompactSupport Ψ ∧ (Icc b c).indicator 1 ≤ Ψ ∧ Ψ ≤ (Ioo a d).indicator 1 ∧ Function.support Ψ = Ioo a d
case h
n : ℕ
A a b c d u x y t σ' : ℝ
ψ Ψ✝ : ℝ → ℂ
F G : ℂ → ℂ
f : ℕ → ℂ
𝕜 : Type
inst✝ : _root_.RCLike 𝕜
h1 : a < b
h3 : c < d
Ψ : ℝ → ℝ
hΨSmooth : Smooth (modelWithCornersSelf ℝ ℝ) (modelWithCornersSelf ℝ ℝ) Ψ
hΨrange : range Ψ ⊆ Icc 0 1
hΨ0 : ∀ (x : ℝ), x ≤ a ∨ d ≤ x ↔ Ψ x = 0
hΨ1 : ∀ (x : ℝ), b ≤ x ∧ x ≤ c ↔ Ψ x = 1
⊢ ContDiff ℝ ⊤ Ψ ∧
    HasCompactSupport Ψ ∧ (Icc b c).indicator 1 ≤ Ψ ∧ Ψ ≤ (Ioo a d).indicator 1 ∧ Function.support Ψ = Ioo a d