Algebra & Equations

Infinite Geometric Sum

Sum of an infinite geometric series (|r| < 1).

Formula

Formula
S = a11 − r

Variables

SymbolDefinitionType & rangeUnitsRole
a₁ first term computed result result
r ratio (|r| < 1) real number (ℝ) input

Try it yourself

Interactive calculator
Result

Worked examples

Example 1
Givenfirst term a₁ = 1, ratio r = 0.5
Result2
Example 2
Givenfirst term a₁ = 4, ratio r = 0.25
Result5.333333333