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- Engr. RonaldLv 74 weeks ago
.3

∑ 2^k

k = 1

= 2^1 + 2^2 + 2^3

= 2 + 4 + 8

= 14 Answer//

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- Jeff AaronLv 71 month ago
Since the series is so short, you can use alex's method: 2 + 4 + 18 = 14

Or, since the series is geometric, you can use the formula for the sum of a geometric series:

a = 2^1 = 2

r = 2

n = 3

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

S = 2(2^3 - 1)/(2 - 1)

S = 2(8 - 1)/1

S = 2*7

S = 14

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