The linearity coefficient of metric projections onto one-dimensional Chebyshev subspaces of the space C

The paper deals with the operator of metric projection onto an arbitrary one-dimensional Chebyshev subspace 〈φ〉 of the space C[K] of real-valued functions defined and continuous on a Hausdorff compact set K. The linearity coefficient of the operator is calculated in terms of the parameters of the generating function φ. As a consequence, a new estimate of the Lipschitz constant of the operator is obtained.