Determine the sum of the following series(adsbygoogle = window.adsbygoogle || []).push({});

[tex]\sum_{n=1}^\infty \frac{2^n+6^n}{9^n}[/tex] or can be written as...

[tex]\sum_{n=1}^\infty \frac{8^n}{9^n}[/tex]

[tex] A_1 = 8/9, A_2 = 64/81, A_3 = 512/729 [/tex]

common ration (r)= 8/9

first term (a)= 8/9

so plugging everything i know into the geometric series formula:

[tex] \frac {a}{1-r}[/tex]

i get.... 8

but it's wrong, and i dont see why

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# Homework Help: Sum of series

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