Let \(A\) be a \(d\times d\) real matrix. State and prove a theorem that gives necessary and
sufficient conditions on \(A\) so that every solution \(x(t)\) is bounded for \(t\in [0,\infty )\).
\[ \dot {x}=Ax. \tag {1} \]
Let \(A(t)\) be a \(C^1\), \(T>0\) periodic, \(d\times d\) real continuous matrix function. State but don’t
prove a theorem that gives necessary and sufficient conditions on \(A(t)\) so that
every solution \(x(t)\) is bounded for \(t\in [0,\infty )\).