SOLUTION: Write 7 Σ81(-1/3)^(k-2) k=2 in expanded form. then find the sum

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Question 1035575: Write
7
Σ81(-1/3)^(k-2)
k=2
in expanded form. then find the sum

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
= 81
= 81*(1 - 1/3 + 1/9 - 1/27 + 1/81 - 1/243)
= 81 - 27 + 9 - 3 + 1 - 1/3
= 182/3