VINCULUM
, in Algebra, a mark or character, either drawn over, or including, or some other way accompanying, a factor, divisor, dividend, &c, when it is compounded of several letters, quantities, or terms, to connect them together as one quantity, and shew that they are to be multiplied, or divided, &c, together.
Vieta, I think, first used the bar or line over the quantities, for a Vinculum, thus ―(a + b); and Albert Girard the parenthesis thus (a + b); the former way being now chiefly used by the English, and the latter by most other Europeans. Thus ―(a + b) X c, or (a + b) X c, denotes the product of c and the sum a + b considered as one quantity. Also √(a + b), or √(a + b), denotes the square root of the sum a + b. Sometimes the mark: is set before a compound factor, as a Vinculum, especially when it is very long, or an infinite series; thus 3a X: 1 - 2x + 3x2 - 4x3 + 5x5 &c.
