Thanks | Mathematics | Page 1

tall moss May 31, 2024, 7:15 AM

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merry locustBOT May 31, 2024, 7:15 AM

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tall moss May 31, 2024, 7:16 AM

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can't find what n is

mint gate May 31, 2024, 8:21 AM

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394822

fallen river May 31, 2024, 8:22 AM

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mint gate 394822

how?

mint gate May 31, 2024, 8:22 AM

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3/(n^0.8) < 0.0001

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implies
n>300000 3^(1/4)

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So n>394822

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You mean why ?

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Or how?

fallen river May 31, 2024, 8:26 AM

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mint gate Or how?

im sorry, gimme a min
lemme understand the quesetion properly

fallen river May 31, 2024, 8:33 AM

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mint gate Or how?

I mean how

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Im not able to understand the question

mint gate May 31, 2024, 8:36 AM

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The series converges (by the alternating series criterion)
So denote by $S$ the sum of this series.

They are asking how many terms should we sum till we get close to S by 0.0001.
This means we want to find the number $k$ of terms to add such that
$|S-S_k| < 0.0001$
Where $S_k = \sum_{n=1}^{n=k} \frac{(-1)^n \times 3}{n^{0.8}}$

#Thanks