摘要
In the paper the estimation of upper and lower bounds of the norm of Hermite interpolatory operstor at the n-the roots of unity is presented: 0<C_(1q)ln n≤‖_((q+1)n-1)‖≤C_(2q) lnn,where q≥0 is a arbirary integer. From that the degree of approximation by Hermite interpolatory polynomials is given. Furthermore,the estimate of approximation to the derivatives of approximated function by the corresponding derivatives of Hermite interpolatory polynomials is also investigated.
