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Calculate the sum of infinity of \(1+\frac{1}{3}±\frac{1}{9}+\frac{1}{27}\)

Calculate the sum of infinity of \(1+\frac{1}{3}±\frac{1}{9}+\frac{1}{27}\)
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  • A 0 .33
  • B 0 .67
  • C 1.5
  • D 2.5
Correct Answer: Option C
Explanation:
The given sequence is a geometric progression with the first term \( a = 1 \) and common ratio \( r = \frac{1}{3} \).

The formula for the sum to infinity of a geometric series is:

\[
S_\infty = \frac{a}{1 - r}
\]

Substituting the values:

\[
S_\infty = \frac{1}{1 - \frac{1}{3}} = \frac{1}{\frac{2}{3}} = \frac{3}{2} = 1.5
\]

Thus, the sum to infinity is 1.5, so the correct answer is C.

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