September 2003:
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September 2003: | |
Find the limit of the following series as n approaches infinity. Show your work:
(1 - 1/2^2) (1 - 1/3^2) ... (1 - 1/n^2). |
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The limit series can be simplified to a succinct expression: (n+1)/2n. For example, taking the first two sets of parantheses, we get 3/4 times 8/9 or 2/3. This is also equal to (3+1)/(2*3) or 2/3. So, at any point in the series, (n+1)/2n gives the result of the last multiplied terms. Thus, we can take the limit of (n+1)/2n as n approaches infinity. The denominator and numinator both have a degree of 1, but since the denominator has a coefficient of 2, the solution is 1/2. | |
Correct Solutions: Andy Young |
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