Some results on zeros of palindromic and perturbed polynomials of even degree

Abstract

In this paper we give necessary and sufficient conditions for all zeros of palindromic polynomial of even degree R(z) = 1 + (z + z2 + ::: + zn−1) + zn, with ∈ R, to be on the unit circle and we find  ∈ R for which S(z) = R(z)+
zn has all its zeros inside or on the unit circle.