B1. Definitions
Infinite series
If an is a sequence of real numbers, then an infinite series is an expression of the
form
The elements in the sum are called terms; an is the nth or general term of the
series.
Example 7 __
p-series
A series of the form is called a p-series.
The p-series for p = 2 is .
BC ONLY
Example 8 __
Harmonic series
The p-series with p = 1 is called the harmonic series:
Example 9 __
Geometric series
A geometric series has a first term, a, and common ratio of terms, r:
Convergent
If there is a finite number S such that