Hi everybody,

f is a positive and continuous function on $\displaystyle \mathbb{R}^+$ such as:

$\displaystyle \lim_{x \to +\infty} \frac{f(x)}{x}=1$.

I must show that the following equation: f(x)=x accepts least one solution in $\displaystyle \mathbb{R}^+$.

Can you help me please?

And thank you anyway.