172k views
4 votes
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".

User Marikit
by
8.0k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories