f(x+f(y))=yf(xy+1)
Source:
January 5, 2009
functionalgebra unsolvedalgebra
Problem Statement
Find all functions such that f: \mathbb{R}^\plus{} \rightarrow \mathbb{R}^\plus{} and f(x\plus{}f(y))\equal{}yf(xy\plus{}1) for every x,y\in \mathbb{R}^\plus{}.