Find all functions $f:\Bbb R$\{0, 1} $\to \Bbb R$, such that $f(x) + 2f(\frac{1}{x}) + 3f(\frac{x}{x-1}) = x$
104278
Finding function $f(x)$ which satisfy given functional equation
14495
I need to find all functions $f:\mathbb R \rightarrow \mathbb R$ which are continuous and satisfy $f(x+y)=f(x)+f(y)$
81799
Examples of functions where $f(ab)=f(a)+f(b)$
29403
Finding functions $f: \Bbb R_*^+ \to \Bbb R_*^+$ with certain properties
136655
Find the range of the given function $f$
60456
Find the power series of $f(x)=\frac{1}{x^2+x+1}$
50833
Find all $f:\mathbb R\to\mathbb R$ such that $\forall x,y\in\mathbb R$ the given equality holds: $xf(y)+yf(x)=(x+y)f(x)f(y)$.
98255
Find $f(x)$ such that $f(f(x)) = x^2 - 2$
39090
Finding functions such that $f(g(x)) = f(x)g(x)$
34343
Determine all $f : \mathbb R \rightarrow \mathbb R$ such that $f(f(x) + y) = f(x^2 - y) + 4yf(x)$.
155531
Entire functions such that $f(z+\lambda_1)=af(z) \; , \; f(z+\lambda_2)=bf(z) $
146719
Functional equation $f(r \cos \varphi)+f(r \sin \varphi)=f(r)$
44293
Functions satisfying $f\left( f(x)^2+f(y) \right)=xf(x)+y$
76458
Solve the following functional equation $f(xf(y))+f(yf(x))=2xy$
6680
Solve for all possible functions f: $|f(x)-f(y)|=2|x-y|$.
11453
Find a real function $f:\mathbb{R}\to\mathbb{R}$ such that $f(f(x)) = -x$?
35556
$f(z)=\frac{z}{1+|z|} $ Is 1-1?