ILoveBaseball
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Determine the sum of the following series
\sum_{n=1}^\infty \frac{2^n+6^n}{9^n} or can be written as...
\sum_{n=1}^\infty \frac{8^n}{9^n}
A_1 = 8/9, A_2 = 64/81, A_3 = 512/729
common ration (r)= 8/9
first term (a)= 8/9
so plugging everything i know into the geometric series formula:
\frac {a}{1-r}
i get... 8
but it's wrong, and i don't see why
\sum_{n=1}^\infty \frac{2^n+6^n}{9^n} or can be written as...
\sum_{n=1}^\infty \frac{8^n}{9^n}
A_1 = 8/9, A_2 = 64/81, A_3 = 512/729
common ration (r)= 8/9
first term (a)= 8/9
so plugging everything i know into the geometric series formula:
\frac {a}{1-r}
i get... 8
but it's wrong, and i don't see why