If $X$ and $Y$ are metric spaces and $X$ is totally bounded and $f:X\to Y$ is continuous (not necessarily uniform), is it true that $f(X)$ is also bounded? How can we prove it or is there any counter example?
I tried:
$f(x)=\tan x$ for $\pi/2<x<\pi/2$, then $X$ is bounded but $f(X)$ is unbounded.
Is my counterexample correct? If not, is there any better counterexample? Or maybe is $f(X)$ bounded and how can we prove it?
Thanks!
That is correct. $1/x$ on $(0,1)$ is easier.