Any solutions to the functional equation?
39090
Finding functions such that $f(g(x)) = f(x)g(x)$
18903
Finding solutions to equation of the form $1+x+x^{2} + \cdots + x^{m} = y^{n}$
144859
Finding parameters for $f(x) = x^2 + 2(m − a)x + 3am −2 = 0$ that satisfy a condition.
31732
If the function $f$ satisfies the equation $f(xf(y)+x)=xy+f(x)$, find $f$
4178
Solve $f(x)f(2x^2) = f(2x^3+x)$
47212
Solving functional equation
111556
Solving functional equation $f(x+y)+f(x-y)=2f(x)\cos y$?
112548
Existence of non-trivial linear functional on any vector space
17175
Problem in solving functional equation $f(x^2 + yf(x)) = xf(x+y)$
100319
Functional equation with strange property about irrational numbers
144042
On the functional square root of $x^2+1$
55693
The functional equation $ f \big( x - f ( y ) \big) = f \big( f ( y ) \big) + x f ( y ) + f ( x ) - 1 $
84318
A problem with the functional $F(\chi) = \int_{\mathbb{R}}(\chi'^2+\chi^2(1-\chi)^2)dx$.
49794
Solve $f(x^2+y+f(y))=2y+f(x)^2$ over $\mathbb{R}$
88683
Functional equation $f\left(\frac{x+y}{2}\right)+f\left(\frac{2xy}{x+y}\right)=f(x)+f(y)$ implies $2f(\sqrt{xy})=f(x)+f(y)$
156778
Finding functions satisfying $f(f(x))+f(x)+x=0$
71049
Functional equation $f(xy)=f(x)+f(y)$ and continuity