English
Analogous tendsto statements hold for tendsto_leftLim and tendsto_rightLim with left and right neighborhoods.
Русский
Аналогичные утверждения о пределностях справедливы для tendsto_leftLim и tendsto_rightLim относительно левых и правых окрестностей.
LaTeX
$$$\operatorname{tendsto}(f,\mathcal{N}_{<}(a), \mathcal{N}(\operatorname{leftLim}(f,a))) \land \operatorname{tendsto}(f,\mathcal{N}_{>}(a), \mathcal{N}(\operatorname{rightLim}(f,a)))$$$
Lean4
theorem tendsto_leftLim (x : α) : Tendsto f (𝓝[<] x) (𝓝 (leftLim f x)) :=
by
rcases eq_or_ne (𝓝[<] x) ⊥ with (h' | h')
· simp [h']
rw [leftLim_eq_sSup hf h']
exact hf.tendsto_nhdsLT x