Tangent

straight biplanar osculating circle trigonometry yaw transverse rabbit hole oscnode blade rolle's theorem point of tangency orbiform intersphere binormal polar normal force cosine unrelated tangential incidental codirection incircle gradient isoptic cotangent sohcahtoa tractrix sine double point pier common radical axis touching gradient wind crossing number hairy ball theorem clavichord horosphere arctangent tactile unode biscribed pedal curve bitangent horn angle transversality hexlet otopy point of interest pseudotriangle tangency osculation line of force gunter's scale tangent space radical line nyckelharpa hypercusp complex binode trope line curve malfatti circle obround topic osculate hyperflex point shen ring involute hyperbola black sanctus midsphere excircle subtangent non sequitur tangents saddle point apollonian gasket semitangent streamline stereographic projection normal tacnode real turning number angle slope branch arc