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The numbers x − 6, 2x and x2 are in G.P. Find nth term

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Question

The numbers x − 6, 2x and x2 are in G.P. Find nth term

Sum
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Solution

nth term = arn−1, where a = 4, r = `x^2/(2x)` = `100/20` = 5

= 4(5)n−1

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Chapter 2: Sequences and Series - Exercise 2.1 [Page 28]

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