English
There is a dual version of grade: grade 𝕆 (ofDual a) = ofDual( grade 𝕆ᵒᵈ a ).
Русский
Существует двойственная версия градации: grade 𝕆 (ofDual a) = ofDual( grade 𝕆ᵒᵈ a ).
LaTeX
$$$\\\\operatorname{grade}_{\\\\mathcal{O}}(\\\\mathrm{ofDual}(a)) = \\\\mathrm{ofDual}(\\\\operatorname{grade}_{\\\\mathcal{O}^\\\\mathrm{op}}(a))$$$
Lean4
@[simp]
theorem grade_ofDual [GradeOrder 𝕆 α] (a : αᵒᵈ) : grade 𝕆 (ofDual a) = ofDual (grade 𝕆ᵒᵈ a) :=
rfl