2. Let X be the normed space whose points are sequences of complex numbers \\
$x = (\xi_i)$ with only finitely nonzero terms and norm defined by $||x|| = \sup_i |\xi_i|$. \\
Let $X \to X$ be defined by \\
$y = Tx = (\xi_1, \frac{1}{2}\xi_2, \frac{1}{3}\xi_3, \dots)$. \\
Then $T$ is linear and bounded but $T^{-1}$ is unbounded.
