I'm trying to understand the following property:
Given an oblique cone (second order), the imaginary circle at infinity can be represented as an imaginary circle with radius equal to the height of the cone and whose center is the orthogonal projection of the cone's vertex over the plane that contains the cone's base (in this case is a conic section). This property is used in the construction of the rectangulars axis for the cone. Could you gime me some explanations or may be a reference to read about this property? Thanks