Question

Compute the sum and the limit of the sum as n -> (infinity sign)

Answer 1

@electrokid can u help

Answer 2

no comprehendo the picture

Answer 3

okay

Answer 4

expand it
\[
S=\sum{i^2\over n^3}+2\sum{i\over n^2}\\
S={1\over n^3}\sum_{i=1}^ni^2+{2\over n^2}\sum_{i=1}^ni
\]
now, apply the formulae for the sums