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What is an alternating series?

A series where the terms alternate in sign.

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What is an alternating series?
A series where the terms alternate in sign.
Define the error bound for an alternating series.
The maximum possible difference between the true sum of the series and a partial sum approximation.
What is a partial sum?
The sum of a finite number of terms of a series.
What is the 'first omitted term' in the context of the Alternating Series Error Bound?
The term immediately following the last term included in the partial sum.
What does 'error bound' represent in the Alternating Series Error Bound Theorem?
It represents the maximum possible error when approximating the infinite sum by a partial sum.
Define a convergent alternating series.
An alternating series that approaches a finite limit as the number of terms increases indefinitely.
What is the significance of 'alternating' in the context of the Alternating Series Error Bound?
It refers to the alternating signs of the terms, which allows for a simple error bound calculation.
What is the purpose of calculating the error bound?
To estimate the accuracy of approximating an infinite series with a finite partial sum.
What is the relationship between the error bound and the number of terms used in the partial sum?
Generally, the more terms used, the smaller the error bound, leading to a more accurate approximation.
What is the role of ( a_i ) in the error bound formula?
\( a_i ) represents the absolute value of the first omitted term, which serves as the error bound.
What is the formula for the Alternating Series Error Bound?
$|s - s_{i-1}| leq a_i$
In the error bound formula, what does ( s ) represent?
The true sum of the infinite alternating series.
In the error bound formula, what does ( s_{i-1} ) represent?
The partial sum of the first ( i-1 ) terms of the series.
What does ( a_i ) represent in the Alternating Series Error Bound formula?
The absolute value of the ( i )-th term of the series (the first omitted term).
What does the inequality ( |s - s_{i-1}| leq a_i ) imply?
The absolute difference between the true sum ( s ) and the partial sum ( s_{i-1} ) is less than or equal to ( a_i ).
How can you express the range in which the true sum ( s ) lies, given the error bound?
By rewriting the inequality as ( s_{i-1} - a_i leq s leq s_{i-1} + a_i ).
What is the formula to calculate the nth term of the alternating series?
If the alternating series is given by $\sum_{n=1}^\infty (-1)^n a_n$, then the nth term is $(-1)^n a_n$.
How do you calculate the partial sum ( s_n ) of an alternating series?
Sum the first ( n ) terms of the series: ( s_n = \sum_{i=1}^n (-1)^i a_i ).
Write the general form of an alternating series.
$\sum_{n=1}^\infty (-1)^n a_n$ or $\sum_{n=1}^\infty (-1)^{n+1} a_n$, where ( a_n > 0 ) for all ( n ).
How can you determine the error bound for the sum of the first ( n ) terms?
The error bound is given by the absolute value of the (n+1)-th term, i.e., ( |a_{n+1}| ).
Explain the concept of estimating the sum of an infinite alternating series.
We use a partial sum to approximate the infinite sum. The Alternating Series Error Bound Theorem helps quantify the accuracy of this approximation.
Why is the Alternating Series Error Bound useful?
It provides a simple way to determine the maximum possible error when using a partial sum to approximate the sum of a convergent alternating series.
What does it mean for an estimation to be 'accurate' in the context of alternating series?
An accurate estimation means that the difference between the estimated value (partial sum) and the true value (infinite sum) is small, as quantified by the error bound.
Why does the Alternating Series Error Bound work?
Because the alternating signs cause the partial sums to oscillate around the true sum, with each term bringing the partial sum closer.
How does the magnitude of terms in an alternating series affect the error bound?
Smaller terms lead to a smaller error bound, indicating a more accurate approximation with fewer terms.
Explain the relationship between the number of terms used and the accuracy of the estimation.
Generally, using more terms in the partial sum leads to a smaller error bound and a more accurate estimation of the infinite sum.
What is the significance of the alternating signs in the context of error estimation?
The alternating signs ensure that the error is no larger than the absolute value of the first omitted term.
What is the role of convergence in the Alternating Series Error Bound?
The series must be convergent for the error bound to provide a meaningful estimate of the accuracy of the partial sum.
Explain why the error bound is the absolute value of the first omitted term.
The oscillating nature of the alternating series causes the partial sums to converge towards the true sum, with each term correcting the previous partial sum by at most the absolute value of that term.
How does the Alternating Series Error Bound relate to the concept of limits?
The error bound provides a way to quantify how close a partial sum is to the limit (true sum) of the infinite alternating series.