The primary motivation of the paper is to define a new class C h δ α , β γ which consists univalent functions associated with Chebyshev polynomials. For this class, we determine coeff...

Let f(z) be analytic on the unit disk, and let p*(z) be the best (Chebyshev) polynomial approximation to f(z) on the disk of degree at most n. It is observed that in typical problems the “error curve,” the image of the unit circle under (f p*)(z), often approximates to a startling degree a perfect circle with winding number n + 1. This phenomenon is approached by consideration of related proble...