OAI/Analysis/AffineBernstein/LocalMaximumSecond.lean
1 declarations, 0 contain sorry, 0 declared as axioms
- lemma
OAI.AffineBernstein.localMax_second_deriv_nonposline 19Source documentation
The second-order necessary condition, proved from the local Taylor remainder. No elliptic estimate is hidden in the maximum principle step.
lemma localMax_second_deriv_nonpos {f : ℝ → ℝ} (hf : ContDiffAt ℝ 2 f 0) (hm : IsLocalMax f 0) : deriv (deriv f) 0 ≤ 0 := by …