1 | initial version |

This is because `Phi(33, Y)`

is still a polynomial in two variables:

```
sage: Phi(33, Y).parent()
Multivariate Polynomial Ring in X, Y over Finite Field of size 8009
```

So, you have to turn it into a one-variable polynomial first:

```
sage: S.<Y> = GF(8009)[]
sage: S(Phi(33, Y))
Y^3 + 6150*Y^2 + 5541*Y + 1175
sage: S(Phi(33, Y)).parent()
Univariate Polynomial Ring in Y over Finite Field of size 8009
sage: S(Phi(33, Y)).roots()
[(898, 1)]
```

Copyright Sage, 2010. Some rights reserved under creative commons license. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.