DuongThiThanhNgan

Tính các giới hạn dãy số sau:

$a/ \lim_{n->+\infty }(\sqrt{5n^{2}+4n-2}-\sqrt{5n^{2}-5n+6})$

$b/ \lim_{n->+\infty }\frac{6.9^{n}-7.4^{n+3}}{3^{2n+1}-5.6^{n-2}}$

$c/ \lim_{n->+\infty }\frac{\sqrt{n} cosn^{3}}{n-3}$

$d/ \lim_{n->+\infty }(\frac{2n+1}{2n-1})^{3n+2}$

$e/ \lim_{n->+\infty }\frac{n^{2}+3n-2}{1+2+...+n}$

$f/ \lim_{n->+\infty }(\sqrt{2}.\sqrt[4]{2}.\sqrt[8]{2}....\sqrt[2n]{2})$