Hi, everyone!


I'm trying to explain the proof of Luroth theorem (every field $L$, s.t. $K\subset L\subset K(t)$, is isomorphic to $K(t)$) to the high-school audience. I'm not going to use such methods as algebraic extensions and complex analysis. Is there any way to prove this fact with only elementary methods?



Elementary Luroth theorem proof?
See here:
<http://math.berkeley.edu/~gbergman/grad.hndts/Luroth.ps>


