Abstract :
The Fourier expansion of a function in the polynomials orthonormal in [−1, 1] with respect to the weight function J(x) exp[u(x)], where J(x) is the weight of the classical Jacobi polynomials and u(x) is a real function satisfying some conditions, is studied. A comparison theorem on equiconvergence of this series with certain trigonometric Fourier series is proved.
