In calculus, the process of finding a function whose derivative is a given function. The term, sometimes used interchangeably with antidifferentiation, is indicated symbolically with the integral sign . (The differential dx usually follows to indicate x as the variable.) The basic rules of integration are: (1) (f + g)dx = fdx + gdx (where f and g are functions of the variable x), (2) kfdx = kfdx (k is a constant), and (3) (C is a constant). Note that any constant value may be added onto an indefinite integral without changing its derivative. Thus, the indefinite integral of 2x is x2 + C, where C can be any real number. A definite integral is an indefinite integral evaluated over an interval. The result is not affected by the choice for the value of C. See also differentiation.
This entry comes from Encyclopædia Britannica Concise.
For the full entry on integration, visit Britannica.com.
Seen & Heard
What made you look up integration? Please tell us what you were reading, watching or discussing that led you here.