Đáp án:
1. 0
2. \(-\frac{1}{2}\)
3. \(-\infty\)
4. \(-\frac{1}{2}\)
Giải thích các bước giải:
1. \(lim \frac{3}{n-2}=lim \frac{\frac{3}{n}}{1-\frac{2}{n}}=0\)
2. \(lim \frac{7^{n}-2}{2^{n}-2.7^{n}}=lim \frac{1-\frac{2}{7^{n}}}{(\frac{2}{7})^{n}-2}=-\frac{1}{2}\)
3. \(lim(2n-3n^{3})=lim (n^{3}(\frac{2}{n^{2}}-3))=lim -3n^{3}=-\infty\)
4. \(lim (\frac{3^{n}-1}{2^{n}-2.3^{n}+1})=lim (\frac{1-\frac{1}{3^{n}}}{(\frac{2}{3})^{n}-2+\frac{1}{3^{n}}})=-\frac{1}{2}\)