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Evaluate the infinite sum

Evaluate the infinite sum-example-1
User Schwa
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2 Answers

2 votes

Answer:

D. it does not converge


User Dave Winer
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5.9k points
6 votes

Answer:

It does not converge.

Explanation:

Given is an infinite geometric series whose first term is a = 4/7 and common ratio is r = 7/6.

The series ∑a·rⁿ converges if we have |r| < 1.

And the series ∑a·rⁿ diverges if we have |r| > 1.

But we can easily check that |r| = 7/6 > 1.

It means the given series diverges, i.e. does not converge.

Hence, option D is correct answer, i.e. It does not converge.

User Gebbissimo
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5.6k points