Question Number 30491 by abdo imad last updated on 22/Feb/18
$${let}\:{A}_{{n}} =\:\sum_{{k}=\mathrm{1}} ^{{n}} \:\:\frac{{n}}{{n}^{\mathrm{2}} \:+{k}^{\mathrm{2}} }\:{find}\:\:{lim}_{{n}\rightarrow\infty} {A}_{{n}} . \\ $$
let-A-n-k-1-n-n-n-2-k-2-find-lim-n-A-n-