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