Algebra
Advanced

Infinite Geometric Series

Sum of an infinite geometric series that converges.

Formula

S=a1r,  r<1S = \frac{a}{1-r}, \; |r|<1

Variables

aFirst term
rCommon ratio

Example

1+½+¼+... = 2

Did You Know?

An infinite series of shrinking terms can add up to a finite total — the resolution of Zeno's ancient paradoxes.