Search results
Results from the WOW.Com Content Network
In calculus, the second derivative, or the second-order derivative, of a function f is the derivative of the derivative of f. Informally, the second derivative can be phrased as "the rate of change of the rate of change"; for example, the second derivative of the position of an object with respect to time is the instantaneous acceleration of ...
Sometimes other equivalent versions of the test are used. In cases 1 and 2, the requirement that f xx f yy − f xy 2 is positive at (x, y) implies that f xx and f yy have the same sign there. Therefore, the second condition, that f xx be greater (or less) than zero, could equivalently be that f yy or tr(H) = f xx + f yy be greater (or less ...
Stated precisely, suppose that f is a real-valued function defined on some open interval containing the point x and suppose further that f is continuous at x. If there exists a positive number r > 0 such that f is weakly increasing on (x − r, x] and weakly decreasing on [x, x + r), then f has a local maximum at x.
To avoid ambiguity, some mathematicians [citation needed] choose to use ∘ to denote the compositional meaning, writing f ∘n (x) for the n-th iterate of the function f(x), as in, for example, f ∘3 (x) meaning f(f(f(x))). For the same purpose, f [n] (x) was used by Benjamin Peirce [14] [11] whereas Alfred Pringsheim and Jules Molk suggested ...
Part I of the theorem then says: if f is any Lebesgue integrable function on [a, b] and x 0 is a number in [a, b] such that f is continuous at x 0, then = is differentiable for x = x 0 with F′(x 0) = f(x 0). We can relax the conditions on f still further and suppose that it is merely locally integrable.
Given its domain and its codomain, a function is uniquely represented by the set of all pairs (x, f (x)), called the graph of the function, a popular means of illustrating the function. [note 1] [4] When the domain and the codomain are sets of real numbers, each such pair may be thought of as the Cartesian coordinates of a point in the plane.
A similar sentiment was expressed by Marvin Bittinger when he prepared the second edition [3] of his textbook: In response to comments from users, the authors have added exercises that require something of the student other than an understanding of the immediate objectives of the lesson at hand, yet are not necessarily highly challenging.
If f : X → Y is any function, then f ∘ id X = f = id Y ∘ f, where "∘" denotes function composition. [4] In particular, id X is the identity element of the monoid of all functions from X to X (under function composition). Since the identity element of a monoid is unique, [5] one can alternately define the identity function on M to be ...