What is an Infinite Series?

An infinite series is a sum of an infinite set of terms.
In an infinite series, we typically write it as:

Divergence and Convergence of an Infinite Series

Suppose that we have the infinite series:

If we try to evaluate the series for a finite amount of terms, for example, when :

We see that the upon adding just the first terms, we see that the final value is closer to .

  • We see that when we consider more terms (above ), we can see that it is much closer to .
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Therefore, we can say that the infinite series converges to .

However, if we try to consider the infinite series:

We can see that as we add more and more terms: