English
The affine subspace s.orthRadius(p) is the subspace orthogonal to the radius vector p−center at p.
Русский
Аффинное подпространство s.orthRadius(p) — это подпространство, ортогональное вектору радиуса p−центр в точке p.
LaTeX
$$$s.orthRadius(p) = \\{x : x \\in P \\mid \\langle p - s.center, x - p \\rangle = 0\\}$$$
Lean4
/-- The affine subspace orthogonal to the radius vector of the sphere `s` at the point `p` (in
the typical cases, `p` lies in `s` and this is the tangent space). -/
def orthRadius (s : Sphere P) (p : P) : AffineSubspace ℝ P :=
.mk' p (ℝ ∙ (p -ᵥ s.center))ᗮ