SOLUTION: Use the formula a(sub1) + a(sub1)r + a(sub1)r^2 + ...+ a(sub1)r^n-1 = a(sub1) 1-r^n/1-r for the nth partial sum of a geometric sequence to find the sume 1 + 2/3 + 4/9 + 8/27 + ...

Algebra ->  Trigonometry-basics -> SOLUTION: Use the formula a(sub1) + a(sub1)r + a(sub1)r^2 + ...+ a(sub1)r^n-1 = a(sub1) 1-r^n/1-r for the nth partial sum of a geometric sequence to find the sume 1 + 2/3 + 4/9 + 8/27 + ...       Log On


   



Question 74591: Use the formula a(sub1) + a(sub1)r + a(sub1)r^2 + ...+ a(sub1)r^n-1 = a(sub1) 1-r^n/1-r for the nth partial sum of a geometric sequence to find the sume 1 + 2/3 + 4/9 + 8/27 + ... + 64/729.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the sum 1 + 2/3 + 4/9 + 8/27 + ... + 64/729.
The last term is (2/3)^6 and it is the 7th terms because the
series begins with (2/3)^0.
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The sum is S(7) = [(2/3)^8 -1]/[(2/3)-1) = 2.8829....
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Cheers,
Stan H.