# Continuity

Contents

Continuous functions are, in essence, functions whose graphs can be drawn without lifting up your pen. This may sound simple, but this is in fact a very rich subject. Learn how continuity is defined using limits, and about a main property of all continuous functions -- the Intermediate value theorem.

See how you score on these 12 practice questions

A function is continuous at a point if its limit at that point exists and is equal to the actual function's value at that point.

Practice your basic understanding of limits and continuity with more complex cases.

Continuous functions are continuous at all of the points in their domains. In essence, these are functions whose graphs can be drawn with a single brush stroke.

The intermediate value theorem states that if a continuous function, f, with an interval, [a, b], as its domain, takes values f(a) and f(b) at each end of the interval, then it also takes any value between f(a) and f(b) at some point within the interval. This is a basic but important property of all continuous functions.

Review your understanding of continuity with some challenge problems.