Question Number 50404 by Abdo msup. last updated on 16/Dec/18
$${find}\:{lim}_{{n}\rightarrow+\infty} \:{U}_{{n}} \:\:{with} \\ $$$${U}_{{n}} =\left(\sum_{{k}=\mathrm{1}} ^{{n}\:} \:{ch}\left(\frac{\mathrm{1}}{\:\sqrt{{k}+{n}}}\right)\right)−{n} \\ $$$$ \\ $$