Communications of the
Korean Mathematical Society CKMS

In this paper, we consider both maximum modulus and minimum modulus on a circle of some polynomials. These give rise to interesting examples that are about moduli of Chebyshev polynomials and certain sums of polynomials on a circle. Moreover, we obtain some root locations of difference quotients of Chebyshev polynomials.

Keywords: modulus, polynomials, difference quotients, Chebyshev poly\-nomials

MSC numbers: Primary 30C10; Secondary 11B83