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

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