Question

how do i find the sum of a series where n=1 to infinite and 1/(1+(2/3)^n) ? ....

Answer 1

The sum for a series of n is the following
the sum of n = 1/2(first term + the last term or the term you go up to)(the term you go up to)

Answer 2

for example lets say a n = n + 1
find the sum for 10 .
s = 1/2(2 + 11) (10)
s = 11(10)
s= 121