Fiber class of a Hirzebruch surface
= Fiber class of a Hirzebruch surface
{title2=$F$}
The fiber class $F$ is the divisor class of a fiber of $\mathbb F_k\to\mathbb P^1$. Its complete linear system gives the ruling.
= Fiber class of a Hirzebruch surface
{title2=$F$}
The fiber class $F$ is the divisor class of a fiber of $\mathbb F_k\to\mathbb P^1$. Its complete linear system gives the ruling.