Continuity Definition Continuity A function is continuous at

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Continuity

Continuity

Definition: Continuity A function is continuous at a number a if That is, 1.

Definition: Continuity A function is continuous at a number a if That is, 1. f(a) is defined 2. exists 3.

Definition: One Sided Continuity A function f is continuous from the right at a

Definition: One Sided Continuity A function f is continuous from the right at a number a if and f is continuous from the left at a if

Definition: Continuity On An Interval A function f is continuous on an interval if

Definition: Continuity On An Interval A function f is continuous on an interval if it is continuous at every number in the interval. (If f is defined on one side of an endpoint of the interval, we understand continuous at the endpoints to mean continuous from the right or continuous from the left).

Theorem If f and g are continuous at a and c is a constant,

Theorem If f and g are continuous at a and c is a constant, then the following functions are also continuous at a: 1. 2. 3. 4. 5. f+g f–g cf fg f / g if g(a) 0

Theorem (a) Any polynomial is continuous everywhere; that is, it is continuous on =

Theorem (a) Any polynomial is continuous everywhere; that is, it is continuous on = (-∞, ∞). (b) Any rational function is continuous whenever it is defined; that is, it is continuous on its domain.

Theorem Any of the following types of functions are continuous at every number in

Theorem Any of the following types of functions are continuous at every number in their domain: Polynomials; Rational Functions, Root Functions; Trigonometric Functions; Inverse Trigonometric Functions; Exponential Functions; and Logarithmic Functions.

Theorem If f is continuous at b and. In other words, , then

Theorem If f is continuous at b and. In other words, , then

Theorem If g is continuous at a and f is continuous at g(a), then

Theorem If g is continuous at a and f is continuous at g(a), then the composite function f(g(x)) is continuous at a.

The Intermediate Value Theorem n Suppose that f is continuous on the f(a) closed

The Intermediate Value Theorem n Suppose that f is continuous on the f(a) closed interval [a, b] f(c)=N and let N be any f(b) number between f(a) and f(b). Then there exists a number c in (a, b) such that f(c) = N. f a c b

Example • Use the Intermediate Value Theorem to show that there is a root

Example • Use the Intermediate Value Theorem to show that there is a root of the given equation in the specified interval.