What is the sum to infinity of the geometric series ?
Answer and explanation
Correct answer: D. 8
**
- Step 1: An infinite geometric series with first term and common ratio converges to the sum .
- Step 2: Determine the initial term and compute common ratio by dividing the second term by the first term.
- Step 3: Substitute into to evaluate the sum: .
Answer
8.
Why not the others: '12' adds rather than subtracts the constant term in the final step in evaluating ; '8/3' uses instead of in the denominator (calculating ); '6' sums only the first two terms () instead of the full infinite series.
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