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Statement

Notation (p. 125): ff is a monic polynomial (1), EE the set where ∣f∣<1|f|<1 and Eˉ\bar E its closure.

Problem 10 (p. 142). "If ff is of the form (1), does there exist a straight line λ\lambda such that the projection of Eˉ\bar E on λ\lambda has measure at most 2? If z0z_0 is a point of Eˉ\bar E lying on a line of support of EE, does Eˉ\bar E contain a point zz such that ∣z−z0∣≥2|z-z_0|\geq2?"

Problem 15 (p. 143) refers back to this problem.

Source. P. Erdős, F. Herzog, G. Piranian, Metric properties of polynomials, J. Analyse Math. 6 (1958), 125--148, doi:10.1007/BF02790232; Problem 10 on p. 142. The copy read is identified on the source card.

Read depth. Claims checked: the problem was read clause by clause on the page image of p. 142 on 2026-10-08. Nothing here is independently reviewed.

Dependencies

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Bears on

  • #1043: the problem is the first question of Problem 10, stated for {∣f∣≤1}\{|f|\le1\}. That set is Eˉ\bar E: ∣f∣|f| has no local minimum where it equals 11, so each point with ∣f∣=1|f|=1 is a limit of points with ∣f∣<1|f|<1 (an observation made here). The second question is not part of the problem.