Dans cette Note on étudie l'enveloppe d'une famille à un paramètre de courbes lisses tangentes à une courbe ayant un cusp semicubique, telles que le rayon de courbure au point de tangence tende vers zéro lorsque ce point approche le cusp. On montre que, génériquement, l'adhérence de cette enveloppe a deux cusps semicubiques au même point, dont l'un est le cusp donné, tangents à une même droite.
In this Note we study the envelope of 1-parameter family of smooth curves tangent to a curve having a semicubic cusp, such that the radius of curvature at the tangency point vanishes when this point approaches the cusp. We show that, generically, the closure of the envelope has two semicubic cusps at the same point, one of which is the given cusp, tangent to the same straight line.
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@article{CRMATH_2002__335_3_249_0, author = {Capitanio, Gianmarco}, title = {On the envelope of 1-parameter families of curves tangent to a semicubic cusp}, journal = {Comptes Rendus. Math\'ematique}, pages = {249--254}, publisher = {Elsevier}, volume = {335}, number = {3}, year = {2002}, doi = {10.1016/S1631-073X(02)02472-X}, language = {en}, url = {http://www.numdam.org/articles/10.1016/S1631-073X(02)02472-X/} }
TY - JOUR AU - Capitanio, Gianmarco TI - On the envelope of 1-parameter families of curves tangent to a semicubic cusp JO - Comptes Rendus. Mathématique PY - 2002 SP - 249 EP - 254 VL - 335 IS - 3 PB - Elsevier UR - http://www.numdam.org/articles/10.1016/S1631-073X(02)02472-X/ DO - 10.1016/S1631-073X(02)02472-X LA - en ID - CRMATH_2002__335_3_249_0 ER -
%0 Journal Article %A Capitanio, Gianmarco %T On the envelope of 1-parameter families of curves tangent to a semicubic cusp %J Comptes Rendus. Mathématique %D 2002 %P 249-254 %V 335 %N 3 %I Elsevier %U http://www.numdam.org/articles/10.1016/S1631-073X(02)02472-X/ %R 10.1016/S1631-073X(02)02472-X %G en %F CRMATH_2002__335_3_249_0
Capitanio, Gianmarco. On the envelope of 1-parameter families of curves tangent to a semicubic cusp. Comptes Rendus. Mathématique, Tome 335 (2002) no. 3, pp. 249-254. doi : 10.1016/S1631-073X(02)02472-X. http://www.numdam.org/articles/10.1016/S1631-073X(02)02472-X/
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