Q. Does the infinite geometric series converge or diverge?1+21+41+81+…Choices:(A) converge(B) diverge
Identify common ratio: To determine if the infinite geometric series converges or diverges, we need to identify the common ratio r of the series.The common ratio is the factor by which each term is multiplied to get the next term.In this series, each term is half the previous term, so the common ratio is 21.
Check convergence criteria: We know that an infinite geometric series converges if the absolute value of the common ratio is less than 1 (|r| < 1).Since the common ratio of our series is 21, and |\frac{1}{2}| < 1, the series converges.
Apply sum formula: The formula for the sum of an infinite geometric series is S=1−ra, where S is the sum, a is the first term, and r is the common ratio.For this series, a=1 and r=21.
Confirm convergence to 2: We can apply the formula to confirm that the series converges to a finite sum. S=1−211=211=2.The series converges to the sum of 2.
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