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The numbers 3, x, and x + 6 form are in G.P. Find nth term

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प्रश्न

The numbers 3, x, and x + 6 form are in G.P. Find nth term

बेरीज
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उत्तर

When x = 6, nth term is given by

tn = arn–1, where a = 3, r = `"x"/3 = 6/3` = 2

∴ tn = 3(2)n–1

When x = – 3, nth term is given by

tn = arn–1, where a = 3, r = `"x"/3 = (-3)/3` = – 1

∴ tn = 3(– 1)n–1

Hence, nth term = 3(2)n–1 or 3(– 1)n–1.

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पाठ 2: Sequences and Series - Exercise 2.1 [पृष्ठ २८]

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बालभारती Mathematics and Statistics 2 (Arts and Science) [English] Standard 11 Maharashtra State Board
पाठ 2 Sequences and Series
Exercise 2.1 | Q 13. (iii) | पृष्ठ २८

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