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Question
Answer the following:
Find k so that k – 1, k, k + 2 are consecutive terms of a G.P.
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Solution
Since k – 1, k, k + 2 are consecutive terms of a G.P., we have,
`"k"/("k" - 1) = ("k" + 2)/"k"`
∴ k2 = (k – 1)(k + 2)
∴ k2 = k2 + k – 2
∴ k – 2 = 0
∴ k = 2.
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