Let Dk, k is a natural number or zero, be the k-th differential operator, defined in Ck(X), X = [0, 1], and let C be a cone in Ck(X). Let us denote δnk (A, C)C(X) := Dkf − DkLnfC(X) linear relative n-width of set A ⊂ Ck(X) in C(X) for Dk with constraint C. In this paper we estimate linear relative n-width of some balls in C(X) for Dk with constraint C = {f ∈ Ck(X) : Dkf ≥ 0}.