Finding Sum of Alternating Series to Desired Accuracy

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To determine how many terms are needed for the alternating series from n=1 to infinity of ((-1)^(n+1))/(n^2) to achieve an error less than 0.0399, the condition 1/n^2 < 0.0399 must be satisfied. This simplifies to n^2 > 25.0626, leading to n > 5.006. Therefore, n must be at least 6 to ensure the desired accuracy. The conclusion is that at least 6 terms of the series are required to meet the specified error threshold.
lindsaygilber
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How many terms of the series do we need to add in order to find the sum to the indicated accuracy?

The alternating series from n=1 to infinity of ((-1)^(n+1))/(n^2)
|error| less than 0.0399
i got it down to 1/n^2 is less than 0.0399 but i can't figure out if n = 5 or n=6... please help:(
 
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If you want 1/n2< 0.0399, then you want 1/0.0399= 25.0626< n2 While it is close hat is NOT true for n= 5.
 
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