一、设数列$ig{a_{n}ig}$ 恒满足不等式$sqrt{n}|a_{n}|leq 3，n=1,2,...$试证明
$$lim_{n o infty} frac{1}{n^{3} }left [left(sum_1^n a_{i} ight) ^{2}+left(sum_2^n a_{i} ight) ^{2}+cdots+left(sum_n^n a_{i} ight) ^{2} ight]=0$$
二、设正项数列$ig{a_{n} ig}$满足$limlimits_{n o infty}frac{a_{n} }{a_{n-1} }=s>0$，试求
$$lim_{n ightarrow ∞}left (frac{sqrt[n]{a_{1}a_{2}......a_{n} } }{a_{n} } ight )^{frac{1}{n} }$$