Đáp án:
Giải thích các bước giải:
\(\begin{array}{l}
2.\lim \frac{{2 + \frac{4}{n}}}{{\frac{2}{n} - 1}} = \frac{2}{{ - 1}} = - 2\\
3.\lim \frac{{{n^2} - 3n + 2}}{{4{n^2} + 12n + 9}} = \lim \frac{{1 - \frac{3}{n} + \frac{2}{{{n^2}}}}}{{4 + \frac{{12}}{n} + \frac{9}{{{n^2}}}}} = \frac{1}{4}\\
4.\lim \frac{{\sqrt {1 - \frac{1}{n} + \frac{2}{{{n^2}}}} }}{{2 + \frac{3}{n}}} = \frac{1}{2}\\
5.\lim \frac{{1 + \sqrt {1 + \frac{1}{{{n^2}}}} }}{{\sqrt {4 + \frac{1}{n}} }} = \frac{2}{2} = 1
\end{array}\)
