functional equation

A functional equation is an equation whose unknowns are functions.

$f(x+y)=f(x)+f(y),f(x\cdot y)=f(x)\cdot f(y)$ are examples of such equations. The systematic study of these didn’t begin before the 1960’s, although various mathematicians have been studying them before, including Euler and Cauchy just to mention a few.

Functional equations appear many , for example, the gamma function and Riemann’s zeta function both satisfy functional equations.

Title	functional equation
Canonical name	FunctionalEquation
Date of creation	2013-03-22 13:06:53
Last modified on	2013-03-22 13:06:53
Owner	jgade (861)
Last modified by	jgade (861)
Numerical id	9
Author	jgade (861)
Entry type	Definition
Classification	msc 39B05
Related topic	Equation