MathDB

Find all functions

f:\mathbb{R}^+ \to \mathbb{R}^+

and plynomials

P(x),Q(x),R(x)

with positive real coefficients such that

Q(-1)=-1

and for all positive reals

x,y

f(\frac{x}{y}+R(y))=\frac{f(x)}{Q(y)}+P(y).

Proposed by Alireza Danaie, Ali Mirazaie Anari Rated 2

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