Solving functional equation $f(x)+f(1/x)=f(x)\cdot f(1/x)$
53024
$f(x)f(1/x)=f(x)+f(1/x)$
34077
Let $f:\mathbb{R}\to\mathbb{R}$ satisfy $f\big(x-f(y)\big)=f\big(f(y)\big)+x\cdot f(y)+f(x)-1$ for all $x,y\in\mathbb{R}$.
98933
Calculating the sum of $f(x) = \sum_{n=0}^{\infty} {n \cdot 2^n \cdot x^n}$
106284
Establishing a Basis for $F[x]/(f(x))$
14277
Proving $f(x)=x\cdot |x|$ is a bijection
6680
Solve for all possible functions f: $|f(x)-f(y)|=2|x-y|$.
133682
Prove that if $f(t)$ satisfies $f(t)=f'(t)$, then $f(t+s)=f(t)f(s)$ for all $t,s\in R$ without using the fact that $f(t)=c\cdot e^t$.
24862
Solving (quadratic) equations of iterated functions, such as $f(f(x))=f(x)+x$
52858
Find $f$ if $ f(x)+f\left(\frac{1}{1-x}\right)=x $
35281
$1992$ IMO Functional Equation problem
147195
Help needed in finding the value of $f(2001)$ in the given functional equation
17154
Does a non-trivial solution exist for $f'(x)=f(f(x))$?
19474
Find all solutions to the functional equation $f(x) +f(x+y)=y+2 $
157744
Cauchy's functional equation with composite function: $gf(x+y)=gf(x)+gf(y)$
64339
Find $f$ where $f'(x) = f(1+x)$
120170
A late-diverging "approximating solution" for a system of functional equations
144773
function $f(x)=x^{-(1/3)}$ , please check whether my solution is correct?