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For the following G.P.s, find Sn 0.7, 0.07, 0.007, .....

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प्रश्न

For the following G.P.s, find Sn

0.7, 0.07, 0.007, .....

योग
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उत्तर

a = 0.7 = `7/10`, r = `0.07/0.7 = 1/10 < 1`

Sn = `("a"(1 - "r"^"n"))/(1 - "r")`, for r < 1

= `(7/10[1 - (1/10)^"n"])/(1 - 1/10)`

= `7/9 (1 - 1/10^"n")`

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अध्याय 2: Sequences and Series - Exercise 2.2 [पृष्ठ ३१]

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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 2.2 | Q 1. (iii) | पृष्ठ ३१

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