Some functional equations in the space of uniform distribution functions.
In the present paper some complex vector functional equations of higher order without parameters and with complex parameters are solved.
The paper is devoted to some functional inequalities related to the exponential mapping.
The functional equation is solved for general solution. The result is then applied to show that the three functional equations , and are equivalent. Finally, twice differentiable solution functions of the functional equation are determined.
Using some results of the theory of functional equations we deduce some properties of the Jacobian sn z function which seem to be new. Some functional equations have also been found which are fulfilled by the sn z function which the author did not find in the literature.
Equation[1] f(x+y) + f (f(x)+f(y)) = f (f(x+f(y)) + f(f(x)+y))has been proposed by C. Alsina in the class of continuous and decreasing involutions of (0,+∞). General solution of [1] is not known yet. Nevertheless we give solutions of the following equations which may be derived from [1]:[2] f(x+1) + f (f(x)+1) = 1,[3] f(2x) + f(2f(x)) = f(2f(x + f(x))).Equation [3] leads to a Cauchy functional equation:[4] phi(f(x)+x) = phi(f(x)) + phi(x),restricted to the graph of the function f,...