1. Tìm lim [3^(n+1) + 2n] / (5 + 3^n) 2. Tìm lim [(3n^2 + n) / (4n^2 – 5)] 04/11/2021 Bởi Maria 1. Tìm lim [3^(n+1) + 2n] / (5 + 3^n) 2. Tìm lim [(3n^2 + n) / (4n^2 – 5)]
1. $\lim\dfrac{3^{n+1}+2^n}{5+3^n}$ $=\lim\dfrac{3.3^n+2^n}{5+3^n}$ $=\lim\dfrac{3+\Big(\dfrac{2}{3}\Big)^n}{\dfrac{5}{3^n}+1}$ $=3$ 2. $\lim\dfrac{3n^2+n}{4n^2-5}$ $=\lim\dfrac{3+\dfrac{1}{n}}{4-\dfrac{5}{n^2}}$ $=\dfrac{3}{4}$ Bình luận
1. `lim [3^(n+1) + 2n] / (5 + 3^n)` `=\lim\frac{3.3^n+2^n}{5+3^n}` `=3` 2. `lim [(3n^2 + n) / (4n^2 – 5)]` `=\lim\frac{3+\frac{1}{n}}{4-\frac{5}{n^2}}=3/4` Bình luận
1.
$\lim\dfrac{3^{n+1}+2^n}{5+3^n}$
$=\lim\dfrac{3.3^n+2^n}{5+3^n}$
$=\lim\dfrac{3+\Big(\dfrac{2}{3}\Big)^n}{\dfrac{5}{3^n}+1}$
$=3$
2.
$\lim\dfrac{3n^2+n}{4n^2-5}$
$=\lim\dfrac{3+\dfrac{1}{n}}{4-\dfrac{5}{n^2}}$
$=\dfrac{3}{4}$
1.
`lim [3^(n+1) + 2n] / (5 + 3^n)`
`=\lim\frac{3.3^n+2^n}{5+3^n}`
`=3`
2.
`lim [(3n^2 + n) / (4n^2 – 5)]`
`=\lim\frac{3+\frac{1}{n}}{4-\frac{5}{n^2}}=3/4`