A note on polynomial approximation in Sobolev spaces
نویسنده
چکیده
Résumé: Pour des domaines étoilés on donne des nouvelles bornes sur les constants dans les inégalités de Jackson pour les espaces de Sobolev. Pour des domaines convexes, les bornes ne dépendent pas de l’excentricité. Pour des domaines non-convexes ayant un point rentrant, les bornes sont uniformes par rapport à l’angle extérieur. L’outil central est un nouvel opérateur de projection sur l’espace des polynomes.
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تاریخ انتشار 1997