English
The inverse of WithZero MulEquiv is given by unzero; it sends an equivalence between WithZero α and WithZero β to an equivalence between α and β.
Русский
Обратное к WithZero MulEquiv задаётся unzero; оно переводит эквивалентность Between WithZero α и WithZero β в эквивальентность между α и β.
LaTeX
$$$\\operatorname{unzero} : (\\mathrm{WithZero}\\alpha \\simeq_* \\mathrm{WithZero}\\beta) \\to (\\alpha \\simeq_* \\beta)$$$
Lean4
/-- The inverse of `MulEquiv.withZero`. -/
abbrev _root_.MulEquiv.unzero [Group β] (e : WithZero α ≃* WithZero β) : α ≃* β :=
_root_.MulEquiv.withZero.symm e