English
The symmetry of the dual antidistrib acts on inl via the dual: (sumLexDualAntidistrib α β).symm (inl (toDual b)) = toDual (inr b).
Русский
Симметрия двойственного антираспределителя действует на inl через двойственность: (sumLexDualAntidistrib α β).symm (inl (toDual b)) = toDual (inr b).
LaTeX
$$$\\bigl(\\text{sumLexDualAntidistrib}_{\\alpha,\\beta}\\bigr).symm(\\mathrm{inl}(\\mathrm{toDual}(b))) = \\mathrm{toDual}(\\mathrm{inr}(b))$$$
Lean4
@[simp]
theorem sumLexDualAntidistrib_symm_inl : (sumLexDualAntidistrib α β).symm (inl (toDual b)) = toDual (inr b) :=
rfl