English
For any p ∈ (I.comap f).minimalPrimes, there exists p' ∈ I.minimalPrimes with comap f p' = p.
Русский
Для любого p ∈ (I.comap f).minimalPrimes найдётся p' ∈ I.minimalPrimes с comap f p' = p.
LaTeX
$$$\exists p' \in I.minimalPrimes,\ Ideal.comap f p' = p$$$
Lean4
theorem exists_minimalPrimes_comap_eq {I : Ideal S} (f : R →+* S) (p) (H : p ∈ (I.comap f).minimalPrimes) :
∃ p' ∈ I.minimalPrimes, Ideal.comap f p' = p :=
by
obtain ⟨p', h₁, h₂, h₃⟩ := Ideal.exists_comap_eq_of_mem_minimalPrimes f p H
obtain ⟨q, hq, hq'⟩ := Ideal.exists_minimalPrimes_le h₂
refine ⟨q, hq, Eq.symm ?_⟩
have := hq.1.1
have := (Ideal.comap_mono hq').trans_eq h₃
exact (H.2 ⟨inferInstance, Ideal.comap_mono hq.1.2⟩ this).antisymm this