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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता ११ वी

Check whether the following sequence is G.P. If so, write tn. 2, 6, 18, 54, …

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प्रश्न

Check whether the following sequence is G.P. If so, write tn.

2, 6, 18, 54, …

बेरीज
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उत्तर

2, 6, 18, 54, …

t1 = 2, t2 = 6, t3 = 18, t4 = 54, …

Here, `"t"_2/"t"_1 = "t"_3/"t"_2 = "t"_4/"t"_3` = 3

∵ the ratio of any two consecutive terms is a constant, hence the given sequence is a Geometric progression.

Here, a = 2, r = 3

tn = arn–1

∴ tn = 2(3n–1)

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पाठ 2: Sequences and Series - Exercise 2.1 [पृष्ठ २७]

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