unfold nearestℤα
a b c : ℤα
this : OneHom.toFun (↑↑inclusion) 0 = 0
⊢ nearestℤα 0 = 0
a b c : ℤα
this : OneHom.toFun (↑↑inclusion) 0 = 0
⊢ (let y := round (2 * rt7⁻¹ * 0.im);
    { z := round (0.re - 2⁻¹ * ↑y), w := y }) =
    0