In mathematics, a quadric, or quadric surface,'s any D-dimensional hypersurface defined as the locus of zeros of a quadratic polynomial. In coordinates = 1 , parabolic cylinder x^2 + 2ay = 0 , A special fact about low-dimensional quadrics's that every real quadric (in any dimension) can be obtained starting from a conic or the hyperbolic paraboloid by applying revolutions, Cartesian products with the real line, and a real affine transformation. Projective geometry In real projective s… (More on Quadric)