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Determine whether the sum to infinity of the following G.P.s exist, if exists find them: -3,1,-13,19,...

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प्रश्न

Determine whether the sum to infinity of the following G.P.s exist, if exists find them:

`-3, 1, (-1)/3, 1/9, ...`

योग
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उत्तर

Here, a = – 3, r = `-1/3`

Since | r | = `|-1/3| = 1/3 < 1`, the sum to infinity of this G.P. exist and 

S = `"a"/(1 - "r")`

= `(-3)/(1 - (-1/3))`

= `(-3)/((4/3))`

= `-9/4`.

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अध्याय 2: Sequences and Series - Exercise 2.3 [पृष्ठ ३३]

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बालभारती Mathematics and Statistics (Arts and Science) Part 2 [English] Standard 11 Maharashtra State Board
अध्याय 2 Sequences and Series
Exercise 2.3 | Q 1. (iii) | पृष्ठ ३३

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