Question

a) The sum of the first 8 terms of a GP is 5 times the sum of first 4 terms. Find the
common ratio.
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Answer 1

Answer:

what is meant by roster method

Answer 2

Answer:

If the number of terms is even, we take 'a\r' and 'ar' as the middle terms and 'r2 'as the common ratio.” Sum of first 8 terms in GP, S8 = a/r7 + a/r5 + a/r3 + a/r + ar + ar3 + ar5+ ar7 S4 = a/r3 + a/r + ar + ar3 by question, S8 = 5S4 …………………………Aug 9, 2014