A Treatise on the Analytic Geometry of Three Dimensions, Volume 1

ax² axes axis by² centre circle circular section coefficients common condition confocal conjugate consecutive points constant coordinates corresponding cosẞ cosy cubic curve of intersection cz² denote determine diameters direction-cosines directrix double point drawn edge ellipse ellipsoid envelope evidently expressed focal conic foci focus geodesic given line Hence hyperbola hyperboloid imaginary infinity last article line joining line of curvature locus meets the surface normal osculating plane paraboloid parallel perpendicular plane at infinity plane curve planes of circular point of contact point x'y'z polar plane pole principal planes proved quadric radii radius of curvature radius vector reciprocal right angles right line ruled surface sphere sphero-conic square substituting surface of revolution tangent plane tangential equation tetrahedron theorem touch triangle umbilic values vanish λ²