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Does the infinite geometric series converge or diverge?\newline1+12+14+18+1 + \frac{1}{2} + \frac{1}{4} + \frac{1}{8} + \ldots\newlineChoices:\newline(A) converge\newline(B) diverge

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Q. Does the infinite geometric series converge or diverge?\newline1+12+14+18+1 + \frac{1}{2} + \frac{1}{4} + \frac{1}{8} + \ldots\newlineChoices:\newline(A) converge\newline(B) diverge
  1. Identify common ratio: To determine if the infinite geometric series converges or diverges, we need to identify the common ratio rr of the series.\newlineThe common ratio is the factor by which each term is multiplied to get the next term.\newlineIn this series, each term is half the previous term, so the common ratio is 12\frac{1}{2}.
  2. Check convergence criteria: We know that an infinite geometric series converges if the absolute value of the common ratio is less than 11 (|r| < 1).\newlineSince the common ratio of our series is 12\frac{1}{2}, and |\frac{1}{2}| < 1, the series converges.
  3. Apply sum formula: The formula for the sum of an infinite geometric series is S=a1rS = \frac{a}{1 - r}, where SS is the sum, aa is the first term, and rr is the common ratio.\newlineFor this series, a=1a = 1 and r=12r = \frac{1}{2}.
  4. Confirm convergence to 22: We can apply the formula to confirm that the series converges to a finite sum. \newlineS=1112=112=2.S = \frac{1}{1 - \frac{1}{2}} = \frac{1}{\frac{1}{2}} = 2.\newlineThe series converges to the sum of 22.

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