Locus (mathematics)

Set of points that satisfy some specified conditions

In geometry, a locus (plural: loci; Latin for 'place, location') is a set of all points (commonly, a line, a line segment, a curve or a surface), whose location satisfies or is determined by one or more specified conditions. The set of the points that satisfy some property is often called the locus of a point satisfying this property. The use of the singular in this formulation is a witness that, until the end of the 19th century, mathematicians did not consider infinite sets.

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