A unique solution for the exact differential equation of nonuniform lines

The purpose of this letter is to establish that the general solution of the telegraphists´ equation for any nonautonomic line is uniquely given by V = [f(x)]²[A + B ∫ dx/{f(x)}³], A and B being boundary constant, if and only if the propagation factor Γ(x) of the line may be expressible as Γ(x) = √2f´´(x)/f(x) where the primes denote derivatives with respect to the distance variable x, and f(x) is any arbitrary function of x characterizing the distributing of nonuniformity of per-unit-length series impedance Z(x) = Z0f(x), Z0being a constant for impedence.