English
In a context with orders, cmpLE on duals flips the order: cmpLE(toDual x)(toDual y) = cmpLE y x.
Русский
Для двойственного порядка cmpLE меняет направление: cmpLE(toDual x)(toDual y) = cmpLE y x.
LaTeX
$$$\\forall x\\ y,\\ cmpLE (toDual x) (toDual y) = cmpLE y x$$$
Lean4
@[simp]
theorem cmpLE_toDual [LE α] [DecidableLE α] (x y : α) : cmpLE (toDual x) (toDual y) = cmpLE y x :=
rfl