Names for the number 0 in English a formal reading of a team's scoresheet. There is no definitive origin for the tennis score name for 0, "love". It firstly occurred in English, is of comparatively recent origin, and is not used in other languages. The most commonly believed hypothesis is that it is derived from English speakers mis-hearing the French "l'œuf", "the egg", which was the name for a score of zero used in French, because the symbol for a zero used on the scoreboard was an elliptical zero symbol, which visually resembled an egg. There is tangential support for this in the use of "duck" as
Zero of a function a "zero locus". In analysis and geometry, any closed subset of formula_32 is the zero set of a smooth function defined on all of formula_32. This extends to any smooth manifold as a corollary of paracompactness. In differential geometry, zero sets are frequently used to define manifolds. An important special case is the case that formula_1 is a smooth function from formula_35 to formula_32. If zero is a regular value of formula_1, then the zero set of formula_1 is a smooth manifold of dimension formula_39 by the regular value theorem. For example, the unit formula_40-sphere in formula_41 is the zero