English
If U and V are submodules of M with U contained in V, then the dual annihilator reverses inclusion: V.dualAnnihilator ⊆ U.dualAnnihilator.
Русский
Пусть U ⊆ V — подмодули M. Тогда антисимметрично относительно двойного аннигилятора: V.dualAnnihilator ⊆ U.dualAnnihilator.
LaTeX
$$$ U \\le V \\;\\Rightarrow\\; V.dualAnnihilator \\le U.dualAnnihilator $$$
Lean4
@[mono]
theorem dualAnnihilator_anti {U V : Submodule R M} (hUV : U ≤ V) : V.dualAnnihilator ≤ U.dualAnnihilator :=
(dualAnnihilator_gc R M).monotone_l hUV