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What is the sum of the geometric sequence 4, 16, 64, ... if there are 8 terms? (6 points)

User Grasingerm
by
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1 Answer

4 votes

Answer:

87380

Explanation:

The sum to n terms of a geometric sequence is


S_(n) =
(a(r^n-1))/(r-1)

where a is the first term and r the common ratio

r =
(16)/(4) = 4 and a = 4, hence


S_(8) =
(4(4^8-1))/(4-1) =
(4(65535))/(4) = 87380

User Nashihu
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8.6k points

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