Vinculum

Encyclopedia : V : VI : VIN : Vinculum

A vinculum is a horizontal line placed over a mathematical expression, used to indicate that it is to be considered a group. Vinculum is Latin for "chain", reflecting the function of the symbol.

Examples of its use include the case of a group of infinitely repeating digits, for example,

[\frac = 0.333333\dots = 0.\overline]

It is also used in common arithmetic to denote that the numerator is being divided by the denominator as a whole group.

[\frac = \frac = 5]

It is also used in the notation of a radical to indicate the radicand whose root is being indicated. In the next case, the quantity [ab+2] is the radicand, and thus has a vinculum over it.

[\sqrt[n]]

The vinculum is also sometimes used in Boolean algebra, where it serves to indicate a group of expressions whose logical result is to be negated, as in

[\overline]

The vinculum should not be confused with a similar-looking vector notation, e.g. [\overrightarrow] "vector from A to B", or [\vec] "vector named a".

From Wikipedia, the Free Encyclopedia. Original article here. Support Wikipedia by contributing or donating.
All text is available under the terms of the GNU Free Documentation License See Wikipedia Copyrights for details.