epsilon-delta definition of a limit

Author:
Daryl Funk
Topic:
Calculus
Illustration of the epsilon-delta definition of a limit.
Input a function f(x) and specify a value x=a. Input the value L of the limit of f(x) as x approaches a. For a given specified tolerance epsilon, find a value delta so that whenever x is in the interval (x - delta, x + delta), then f(x) is in the interval (L + epsilon, L - epsilon).