What is the sum to infinity of the geometric series ?
Answer and explanation
Correct answer: B. 18
**
- 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
18.
Why not the others: '9' divides the first term by common ratio (calculating ) instead of ; '18/5' uses instead of in the denominator (calculating ); '10' sums only the first two terms () instead of the full infinite series.
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