Abstract:
Sharp estimates are given for the convergence rate of Fourier series in terms of classical orthogonal polynomials in some classes of functions characterized by a generalized modulus of continuity in the space $L_2((a,b),p(x))$. Expansions in terms of Laguerre, Hermite, and Jacobi polynomials are considered.
Key words:Fourier series, generalized modulus of continuity, width, generalized derivatives, expansions in terms of Laguerre, Hermite, Jacobi polynomials, convergence of series.