# Radius of Convergence

The radius of convergence of a power series is half the width of the interval inside which it converges absolutely.

Radius of convergence is a college-level concept that would be first encountered in a Calculus II course. It is an Advanced Placement Calculus BC topic and is listed in the California State Standards for Calculus.

### Prerequisites

Power Series: | A power series is a sum of powers of a variable. A power series is essentially an infinite polynomial. |

Taylor Series: | A Taylor series is a power series of a function around a given point. |