Editing Origin (mathematics) (section)

==Other coordinate systems==
In a [[polar coordinate system]], the origin may also be called the pole. It does not itself have well-defined polar coordinates, because the polar coordinates of a point include the angle made by the positive ''x''-axis and the ray from the origin to the point, and this ray is not well-defined for the origin itself.<ref>{{citation|title=Encyclopedia of Mathematics|first=James Stuart|last=Tanton|publisher=Infobase Publishing|year=2005|isbn=9780816051243|url=https://books.google.com/books?id=MfKKMSuthacC&pg=PA400}}.</ref>

In [[Euclidean geometry]], the origin may be chosen freely as any convenient point of reference.<ref>{{citation|title=Axiomatic Geometry|volume=21|series=Pure and Applied Undergraduate Texts|first=John M.|last=Lee|publisher=American Mathematical Society|year=2013|isbn=9780821884782|page=134|url=https://books.google.com/books?id=9Z0xAAAAQBAJ&pg=PA134}}.</ref>

The origin of the [[complex plane]] can be referred as the point where [[real axis]] and [[imaginary axis]] intersect each other. In other words, it is the [[complex number]] [[zero]].<ref>{{citation|title=Classical Complex Analysis|series=Chapman & Hall Pure and Applied Mathematics|first=Mario|last=Gonzalez|publisher=CRC Press|year=1991|isbn=9780824784157}}.</ref>