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Test the series for convergence or divergence. Σ[infinity] n = 0 (−1)^n + /√1 n + 8. O converges O diverges

1 Answer

1 vote

Answer:

converges

Explanation:

The given series is:

Σn=0 to infinity (-1)^n + / √(1n + 8)

To determine if the series converges or diverges, we can use the comparison test, which involves comparing the given series to a known convergent or divergent series.

Let's compare the given series to a known convergent series. We know that the series Σ1/n^p converges if p > 1. In this case, the series Σ1/n^(1/2) is known to converge since (1/2) > 1.

Let's rewrite the given series in the form Σ1/n^p to compare:

Σn=0 to infinity (-1)^n + / √(1n + 8)

= Σn=0 to infinity (-1)^n + / (1n + 8)^(1/2)

Now we can use the comparison test by comparing the given series to the convergent series Σ1/n^(1/2). Since the terms of the given series are positive (taking the absolute value of (-1)^n), we can ignore the negative sign.

|(-1)^n + / (1n + 8)^(1/2)| ≤ 1 / (1n + 8)^(1/2) (taking absolute values)

As n approaches infinity, 1/(1n + 8)^(1/2) approaches 0, and since 0 is less than 1, the given series is also smaller than the convergent series Σ1/n^(1/2).

Therefore, by the comparison test, the given series converges since it is smaller than the convergent series Σ1/n^(1/2). So the correct answer is "converges".

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