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Determine whether the sum to infinity of the following G.P.s exist, if exists find them: 9, 8.1, 7.29, ...

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प्रश्न

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

9, 8.1, 7.29, ...

बेरीज
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उत्तर

Here, a = 9, r = 0.9

Since l r l = | 0.9 | = 0.9 < 1, the sum to infinity of this G.P. exist and

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

= `9/(1 - 0.9)`

= `9/0.1`

= 90.

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

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