conv => lhs; arg 1; intro x
case succ.h
f : ℝ → ℝ
n : ℕ
h : iteratedDeriv n (-f) = -iteratedDeriv n f
x : ℝ
⊢ deriv (-iteratedDeriv n f) x = (-deriv (iteratedDeriv n f)) x
case succ.h
f : ℝ → ℝ
n : ℕ
h : iteratedDeriv n (-f) = -iteratedDeriv n f
x : ℝ
⊢ deriv (fun x => (-iteratedDeriv n f) x) x = (-deriv (iteratedDeriv n f)) x