English
Characterizes membership in adjoin F (Set.range i) by existential polynomials over i.
Русский
Характеризует принадлежность к адъюнкту через существующие полиномы над i.
LaTeX
$$$x \in \operatorname{adjoin}_F (\operatorname{Set.range} i) \\iff \\exists r,s : MvPolynomial ι F, x = MvPolynomial.aeval i r / MvPolynomial.aeval i s$$$
Lean4
theorem mem_adjoin_range_iff {ι : Type*} (i : ι → E) (x : E) :
x ∈ adjoin F (Set.range i) ↔ ∃ r s : MvPolynomial ι F, x = MvPolynomial.aeval i r / MvPolynomial.aeval i s := by
simp_rw [mem_adjoin_iff_div, Algebra.adjoin_range_eq_range_aeval, AlgHom.mem_range, exists_exists_eq_and]