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Find the Sum of the Following Serie to Infinity: 1 − 1 3 + 1 3 2 − 1 3 3 + 1 3 4 + . . . ∞ - Mathematics

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प्रश्न

Find the sum of the following serie to infinity:

\[1 - \frac{1}{3} + \frac{1}{3^2} - \frac{1}{3^3} + \frac{1}{3^4} + . . . \infty\]

उत्तर

\[\text {  In the given G . P . , first term, } a = 1 \]

\[\text { and common ratio } , r = - \frac{1}{3}\]

\[\text { Hence, the sum S to infinity is given by } S = \frac{a}{1 - r} = \frac{1}{1 - \left( - \frac{1}{3} \right)} = \frac{3}{4} . \]

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अध्याय 20: Geometric Progression - Exercise 20.4 [पृष्ठ ३९]

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आरडी शर्मा Mathematics [English] Class 11
अध्याय 20 Geometric Progression
Exercise 20.4 | Q 1.1 | पृष्ठ ३९

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