First order asymptotic formulas for the best constants in inequalities of the Markov type with L^2 norms for partial derivatives of polynomials in several variables are derived. The principal coefficient in the leading term of the formulas is identifed as the operator norm of a Volterra integral operator and is studied in detail.
Keywords:
Markov inequality, orthogonal polynomials, Volterra integral operators, partial differential operator, polynomials of several variables