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avatar+49 

Find the infinite sum of
1/7+2/7^2+1/7^3+2/7^4...

 Jun 20, 2018

Best Answer 

 #2
avatar+49 
+1

ok, now I know. its the sum of 2 geometric series: (1/7+1/7^3+1/7^5...) + (2/7^2+2/7^4+2/7^6...)

the first part is equal to 7/48, the second part is equal to 2/48, and they add to 9/48, which is 3/16.

yayy

 Jun 20, 2018
 #1
avatar+49 
0

argh, still don't know how to do this!angry

 Jun 20, 2018
 #2
avatar+49 
+1
Best Answer

ok, now I know. its the sum of 2 geometric series: (1/7+1/7^3+1/7^5...) + (2/7^2+2/7^4+2/7^6...)

the first part is equal to 7/48, the second part is equal to 2/48, and they add to 9/48, which is 3/16.

yayy

kevbamboo Jun 20, 2018

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