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What is the trick for proving convergency with Bernoulli's Inequality?

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Final answer:

To prove convergence with Bernoulli's inequality, we need to show that a series is bounded above by another series which converges.

We can use Bernoulli's inequality to find a series that bounds the given series and converges. For example, the series ∑(1/n^2) is bounded above by the convergent geometric series ∑(1/2^n).

Step-by-step explanation:

To prove convergence with Bernoulli's inequality, we need to show that a series is bounded above by another series which converges.

Bernoulli's inequality states that for any real number x ≥ -1 and any positive integer n, (1 + x)^n ≥ 1 + nx.

Let's suppose we have a series ∑a_n. If we can find a number r such that |a_n| ≤ r^n for all n and the series ∑r^n converges, then we can conclude that the series ∑a_n also converges.

This is because the series can be bounded above by a convergent geometric series with a common ratio between -1 and 1.

For example, consider the series ∑(1/n^2). We can bound this series above by ∑(1/2^n), as for all n, (1/2^n) ≤ (1/n^2). Since ∑(1/2^n) is a convergent geometric series, we can conclude that the series ∑(1/n^2) also converges.

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