Infinite Sum Calculator

Calculate Infinite Series with Convergence Testing

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Analyze infinite series convergence and calculate sums for geometric series, p-series, and other mathematical series with step-by-step explanations.

Infinite Sum Calculator

Calculate infinite series with convergence testing

Geometric series: ∑(n=0 to ∞) a·r^n = a + ar + ar² + ar³ + ...
Series Types & Convergence

Geometric Series

Converges when |r| < 1, diverges when |r| ≥ 1. Sum = a/(1-r) when convergent.

p-Series

Converges when p > 1, diverges when p ≤ 1. Famous examples include Basel problem (p=2, sum=π²/6).

Alternating Series

May converge even when the corresponding positive series diverges, tested using the Alternating Series Test.

Supported Series Types

Convergent Series

  • • Geometric Series: ∑ a·r^n (|r| < 1)
  • • p-Series: ∑ 1/n^p (p > 1)
  • • Alternating Series: ∑ (-1)^n·a_n
  • • Basel Problem: π²/6
  • • Exponential Series: e^x expansion

Convergence Tests

  • • Ratio Test for geometric-like series
  • • Comparison Test for p-series
  • • Alternating Series Test
  • • Built-in convergence analysis
  • • Step-by-step explanations

Frequently Asked Questions

What is an infinite series?

An infinite series is the sum of infinitely many terms. The key question is whether this infinite sum converges to a finite value or diverges to infinity.

How do I know if a series converges?

For geometric series, convergence occurs when |r| < 1. For p-series, convergence occurs when p > 1. Our calculator automatically tests convergence for supported series types.

What's the difference between convergent and divergent series?

A convergent series approaches a finite sum as you add more terms. A divergent series either grows without bound or oscillates without settling on a value.

Can I calculate partial sums?

Yes! The calculator shows partial sums (first n terms) to help visualize how the series approaches its limit, along with the theoretical infinite sum for convergent series.

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