Solution
= Solution
Let $\phi_t(x)$ denote the <flow map>[flow] through $x$. Its <alpha-limit set> and <omega-limit set> are
$$
\alpha(x)=\bigcap_{T<0}\overline{\{\phi_t(x):t<T\}},
\qquad
\omega(x)=\bigcap_{T>0}\overline{\{\phi_t(x):t>T\}}.
$$
Equivalently, they contain the limits of $\phi_{t_j}(x)$ along sequences $t_j\to-\infty$ and $t_j\to+\infty$, respectively.