Find the value of a function that satisfy $f(x+1)=f(x)\cdot f(y)$, for all $x,y\in\mathbb{R}$.
22303
How do I prove that $f(x)f(y)=f(x+y)$ implies that $f(x)=e^{cx}$, assuming f is continuous and not zero?
146719
Functional equation $f(r \cos \varphi)+f(r \sin \varphi)=f(r)$
129052
Find all functions satisfying $\frac{1}{f(a)}+ \frac{1}{f(b)} = \frac{1}{f(c)} $ whenever $\frac{1}{a}+ \frac{1}{b} = \frac{1}{c} $
110704
Find all functions $f$ such that $f(x)+f(\frac{1}{1-x})=x$
129599
Functional Equation: Find all functions $f: \mathbb{R} \rightarrow \mathbb{R}$ such that $(x+y)(f(x)-f(y))=(x-y)f(x+y)$
99917
What function satisfies $F'(x) = F(2x)$?
126931
Find $f(x)$ such that $f(x)+f\left(\frac{1}{x}\right)=f(x)\cdot f\left(\frac{1}{x}\right)$
28286
About finding the function such that $f(xy)=f(x)f(y)-f(x+y)+1$
72769
How find this function $xf(x^2)=f(x),x>0$
84143
Given any function $g(x): \mathbb{R} \rightarrow \mathbb{R}$, find a function $f(x)$ such that $f(f(x)) = g(x)$.
23465
When $f(x+1)-f(x)=f'(x)$, what are the solutions for $f(x)$?
122407
If $f(x) = x^3+3x+4\;,$ Then value of $ \int_{-1}^{1}f(x)dx+\int_{0}^{4}f^{-1}(x)dx$
97772
An example of a function which satisfies $\sup_{y}\inf_{x}f(x,y)<\inf_{x}\sup_{y}f(x,y)$
118565
Find a function value given 2 points
64339
Find $f$ where $f'(x) = f(1+x)$
41226
Find $f:f(xf(x)+f(y))=f(x)^2+y$
73519
Determine all functions satisfying $f(x + f(x + y)) + f(xy) = x + f(x + y) +yf(x)$