On the extremal problem about the minimum of the free term of a nonnegative trigonometric polynomial

A new extremal problem is solved about the minimum of the free term of a nonnegative even trigonometric polynomial with the following conditions on its coefficients: all coefficients except for the free term are greater than or equal to 1 and the sum of all coefficients except for the free term is equal to a specified value. As a result, Fejér's known result is improved.