English
If a ∈ s and a ≤ b for all b ∈ s, then hs.min (nonempty_of_mem ha) = a.
Русский
Если a ∈ s и a ≤ b для всех b ∈ s, тогда hs.min (nonempty_of_mem ha) = a.
LaTeX
$$$hs.min\\, (nonempty_of_mem ha) = a$$$
Lean4
theorem min_eq_of_le (hs : s.IsWF) (ha : a ∈ s) (hle : ∀ b ∈ s, a ≤ b) : hs.min (nonempty_of_mem ha) = a :=
(eq_of_le_of_not_lt (hle (hs.min (nonempty_of_mem ha)) (hs.min_mem (nonempty_of_mem ha)))
(hs.not_lt_min (nonempty_of_mem ha) ha)).symm