Solution using $f\left( x \right) = x\cos \frac{1}{x},x \ge 1$
105999
An application of derivatives problem- to show that $f(x+2)-f(x)>2$ for $f(x)=x\cos(1/x)$
144329
Help solving a limit in two parts $\lim_{t\to 0}\left(\frac{1}{t\sqrt{1+t}}-\frac{1}{t}\right)$
20568
Does the following have a solution for f(x,y)?
106742
Evaluating $ \lim_{x \rightarrow 0}\left (\frac{\sin(x)}{x}\right)^\frac{1}{x^2}$
131847
$\frac{(x-1)(x+1)}{ (x+1)} \rightarrow (x-1)$ Domain Change
111556
Solving functional equation $f(x+y)+f(x-y)=2f(x)\cos y$?
23217
About $\lim \left(1+\frac {x}{n}\right)^n$
147977
Evaluate $\int_0^1\left(\frac{x-1}{x+1}\right)^n\frac{1}{\ln x} \,dx$
51864
$\left( \frac{1 \cdot 2}{p} \right) + \left( \frac{2 \cdot 3}{p} \right) + \cdots + \left( \frac{(p-2)(p-1)}{p} \right) = -1$
111789
Solving functional differential equation $f'(x)=2f(2x)-f(x)$
39461
What is the solution of $\cos(x)=x$?
44293
Functions satisfying $f\left( f(x)^2+f(y) \right)=xf(x)+y$
26617
Minimum value of $ f(x,y,z)=\left(x+\frac{1}{y}\right)^2+\left(y+\frac{1}{z}\right)^2+\left(z+\frac{1}{x}\right)^2. $
66247
Proving inequality $\left( \frac {x} {y}\right) ^{x}\left( \frac {1-x} {1-y}\right) ^{1-x}\geqslant 1$
76458
Solve the following functional equation $f(xf(y))+f(yf(x))=2xy$
69734
how to find all functions such that $f\left( x^{2} - y^{2} \right) = ( x - y )( f(x) + f(y) )$
53748
Find maximum value of $\int_{0}^{1}\left(f(x)\right)^3dx$