Best exponents in Markov's inequalities

By means of weakly equilibrium Cantor-type sets, solutions of two problems related to polynomial inequalities are presented: the problem by M. Baran et al. about a compact set K ⊂ double-struck C such that the Markov inequality is not valid on K with the best Markov's exponent, and the problem by L. Frerick et al. concerning compact sets satisfying the local form of Markov's inequality with a given exponent, but not satisfying the global version of Markov's inequality with the same parameter. © ELEMENT.