English
Under the same hypotheses, the left-endpoint limit equality holds as a simp consequence.
Русский
При тех же предположениях равенство предела слева следует как следствие упрощения.
LaTeX
$$eq_lim_at_left_extendFrom_Ioo… (simp lemma).$$
Lean4
protected theorem closure (h : IsMaxOn f s a) (hc : ContinuousOn f (closure s)) : IsMaxOn f (closure s) a := fun x hx =>
ContinuousWithinAt.closure_le hx ((hc x hx).mono subset_closure) continuousWithinAt_const h