MathDB
functional ecuation, a bit strange, but not difficult

Source: Third Zhautykov Olympiad, Kazakhstan, 2007

April 25, 2007
functiontrigonometrygeometrygeometric transformationalgebra proposedalgebra

Problem Statement

Does there exist a function f:RRf: \mathbb{R}\rightarrow\mathbb{R} such that f(x+f(y))=f(x)+sinyf(x+f(y))=f(x)+\sin y, for all reals x,yx,y ?