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Question
Find the sum of the following serie to infinity:
8 + \[4\sqrt{2}\] + 4 + ... ∞
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Solution
\[\text { In the given G . P . , first term, } a = 8\]
\[ \text { and common ratio, } r = \frac{1}{\sqrt{2}}\]
\[\text { Hence, the sum S to infinity is given by } S = \frac{a}{1 - r} = \frac{8}{1 - \frac{1}{\sqrt{2}}} = \left( 2 + \sqrt{2} \right) . \]
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