English
Under appropriate domain conditions, RatFunc becomes a field with an embedding that respects field operations and passes through fractions.
Русский
При подходящих условиях область RatFunc образует поле с вложением, сохраняющим операции поля и дроби.
LaTeX
$$$\\text{RatFunc } K \\text{ carries a field structure with consistent algebra }$$
Lean4
@[stacks 09FK]
instance instField [IsDomain K] : Field (RatFunc K)
where
inv_zero := by frac_tac
div := (· / ·)
div_eq_mul_inv := by frac_tac
mul_inv_cancel _ := mul_inv_cancel
zpow := zpowRec
nnqsmul := _
nnqsmul_def := fun _ _ => rfl
qsmul := _
qsmul_def := fun _ _ => rfl