have := support_deriv_subset (f := fun x ↦ f x)
𝕂 : Type u_1
inst✝ : _root_.RCLike 𝕂
a b : ℝ
f : ℝ → 𝕂
fSupp : support f ⊆ Icc a b
⊢ support (deriv f) ⊆ Icc a b
𝕂 : Type u_1
inst✝ : _root_.RCLike 𝕂
a b : ℝ
f : ℝ → 𝕂
fSupp : support f ⊆ Icc a b
this : support (deriv fun x => f x) ⊆ tsupport fun x => f x
⊢ support (deriv f) ⊆ Icc a b