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If the common ratio of a G.P. is 23 and sum to infinity is 12. Find the first term

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प्रश्न

If the common ratio of a G.P. is `2/3` and sum to infinity is 12. Find the first term

योग
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उत्तर

r = `2/3`, sum to infinity = 12    ...[Given]

Sum to infinity = `"a"/(1 - "r")`

∴ 12 = `"a"/(1 - 2/3)`

∴  a = `12 xx 1/3`

∴ a = 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 3 | पृष्ठ ३३

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