projective space

In mathematics a projective space is a set of elements constructed from a vector space such that a distinct element of the projective space consists of all non-zero vectors which are equal up to a multiplication by a non-zero scalar. A formal definition of a projective space can be formulated in several ways, and can also be made more abstract, see below. The projective space generated from a particular vector space V is often denoted P(V). The cases when V=R2 or V=R3 are the projective line and the projective plane, respectively.
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