Verified Answer :

padawan

9 - 6 + 4 - 8/3 ..,

geometric series a(n) = a1r^(n-1)


r = a(n+1)/a(n)

-6/9 = -2/3

4/-6 = -2/3

-8/3/4 = -2/3

so r = -2/3 and a1 = 9


Sn = a1(1-r^n)/(1-r) = 9(1-(-2/3)^n)/(1-(-2/3))

n is infinite Sn = 9/(5/3) = 27/5

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