proposition: Lemma continuity_open_interval_tan : continuity_open_interval (- PI / 2) (PI / 2) tan.
proof: Proof. intros ; apply derivable_in_continuity_in, derivable_open_interval_tan. Qed.
imports: Rbase Rtactic Lra Ranalysis Ranalysis5 Rtrigo AltSeries Rfunctions Rinterval Ranalysis_def Ranalysis_def_simpl Ranalysis_facts Rextensionality Rpser_usual Rsequence_cv_facts MyRIneq Tactics