The rational-function field F3(t)\mathbb F_3(t) is the of the . An element is a quotient a(t)/b(t)a(t)/b(t), with a,b∈F3[t]a,b\in\mathbb F_3[t] and b≠0b\ne0; two fractions agree when cross multiplication gives the same polynomial.

Global and local roles

This is a . Its places include those attached to monic and the place at infinity. Completing at (t)(t) gives , which is a different field.

Scalar conventions

The constants embed as F3\mathbb F_3. A homomorphism over the constant field fixes these constants, while an abstract field map need not fix each of them when qq is not prime. No topology is part of this bare global-field record.