On the positivity of some bilinear functionals in Sobolev spaces
作者：
Highlights：
•
摘要
The positivity of a bilinear functional aa(f,g)=∑Nm=0λmC(m)(fm,gm) is studied as a function of coefficients λm. The concerned cases are those of Laguerre, Gegenbauer and Jacobi for c(m) = c(0), m = 1,…,N. The domain λmm=1N where a is positive definite, is given. As a consequence, when N = 1, the corresponding Markov-Bernstein inequalities are given.
论文关键词：33C45,42C05,26D05,26C10,Formal orthogonal polynomial,Laguerre,Gegenbauer,Jacobi polynomial,Laguerre-Sobolev,Gegenbauer-Sobolev,Jacobi-Sobolev polynomial,Definite inner product,Markov-Bernstein inequality,Zeros of polynomial
论文评审过程：Received 13 May 1998, Revised 30 January 1999, Available online 20 September 2000.
论文官网地址：https://doi.org/10.1016/S0377-0427(99)00063-1
