have : (z.w : ℝ) = 0
case mp.w
a b c z : ℤα
h : OneHom.toFun (↑↑inclusion) z = 0
⊢ z.w = 0.w
case this
a b c z : ℤα
h : OneHom.toFun (↑↑inclusion) z = 0
⊢ ↑z.w = 0

case mp.w
a b c z : ℤα
h : OneHom.toFun (↑↑inclusion) z = 0
this : ↑z.w = 0
⊢ z.w = 0.w