Let $B$ be an Infinite dimensional Banach Space and $T:B\to B$ be an continuous operator such that $T(B)=B$ and $T(x)=0\Rightarrow x=0$
which of the following is correct?
$T$ maps bounded sets into compact set
$T^{-1}$ maps bounded sets into compact set
$T^{-1}$ maps bounded sets into bounded set
$T$ maps compact sets into open set I have no idea how to do it.
$1.$ and $2.$ are not satisfied by $Tx=x$.
$3.$ $T^{-1}$ is bounded (as a consequence of the closed graph theorem).
$4.$ Take $K:=\{0\}$.