Polynomial approximation with exponential weights
โ Scribed by Z. Ditzian; D. S. Lubinsky; P. Nevai; V. Totik
- Publisher
- Akadmiai Kiad
- Year
- 1987
- Tongue
- English
- Weight
- 533 KB
- Volume
- 50
- Category
- Article
- ISSN
- 1588-2632
No coin nor oath required. For personal study only.
๐ SIMILAR VOLUMES
It is shown that if weighted polynomials w n P n with deg P n n converge uniformly on the support of the extremal measure associated with w, then they converge to 0 everywhere else. It is also shown that uniform approximation on the support can always be characterized by a closed subset Z having the
We consider exponential weights of the form w :=e &Q on (&1, 1) where Q(x) is even and grows faster than (1&x 2 ) &$ near \1, some $>0. For example, we can take where exp k denotes the kth iterated exponential and exp 0 (x)=x. We prove Jackson theorems in weighted L p spaces with norm & fw& Lp(&1,
We consider exponential weights of the form w :=e &Q on [&1, 1] where Q(x) is even and grows faster than (1&x 2 ) &$ near \1, some $>0. For example, we can take where exp k denotes the kth iterated exponential and exp 0 (x)=x. We prove converse theorems of polynomial approximation in weighted L p s