\(S=1+\dfrac{1}{2}+\dfrac{1}{2^2}+...+\dfrac{1}{2^n}=\dfrac{1}{1-\dfrac{1}{2}}=2\)
Khi đó : Lim S = Lim 2 = 2
\(S=1+\dfrac{1}{2}+\dfrac{1}{2^2}+...+\dfrac{1}{2^n}=\dfrac{1}{1-\dfrac{1}{2}}=2\)
Khi đó : Lim S = Lim 2 = 2
Tìm giới hạn các dãy số sau
a) \(lim\dfrac{2^n+6^n-4^{n-1}}{3^n+6^{n+1}}\)
b) \(lim\dfrac{1+3+5+...+\left(2n+1\right)}{3n^2+4}\)
c) \(lim\dfrac{1+2+3+...+n}{n^2-3}\)
d) \(lim\left[\dfrac{1}{1.2}+\dfrac{1}{2.3}+...+\dfrac{1}{n\left(n+1\right)}\right]\)
e) \(lim\left[\dfrac{1}{1.3}+\dfrac{1}{3.5}+...+\dfrac{1}{\left(2n-1\right)\left(2n+1\right)}\right]\)
Tìm giới hạn dãy số sau
\(lim\dfrac{\left(2n-1\right)\left(3n^2+2\right)^3}{-2n^5+4n^3-1}\)
\(lim\left(3.2^{n+1}-5.3^n+7n\right)\)
Tìm giới hạn :
lim \(\left[1+\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{16}+...+\dfrac{1}{n^2}\right]\)
Tính các giới hạn sau:
\(a.lim\left(\dfrac{\left(n-1\right)!+n!+3}{\left(n+2\right)!-\left(n-2\right)!}\right)\)
b.\(lim\left(\dfrac{2n+1}{n\cdot3^n}\right)\)
Tính các giới hạn
a) \(lim\dfrac{1+\dfrac{1}{3}+\left(\dfrac{1}{3}\right)^2+...+\left(\dfrac{1}{3}\right)^n}{1+\dfrac{1}{2}+\left(\dfrac{1}{2}\right)^2+...+\left(\dfrac{1}{2}\right)^n}\)
\(lim\left(n^3+n\sqrt{n}-5\right)\)
Giúp mình với ạ
Tính các giới hạn
a) \(\lim\limits_{x\rightarrow\infty}\dfrac{a_0x^m+a_1x^{m-1}+a_2x^{m-2}+...+a_m}{b_0x^n+b_1x^{n-1}+b_2x^{n-2}+...+b_n}\)
b) \(\lim\limits_{x\rightarrow+\infty}\dfrac{\left(x-\sqrt{x^2-1}\right)^n+\left(x+\sqrt{x^2-1}\right)^n}{x^n}\)
tính giới hạn
1.\(\lim\limits\left(n^3+4n^2-1\right)\)
2.\(lim\dfrac{\left(n+1\right)\sqrt{n^2-n+1}}{3n^2+n}\)
3.\(lim\dfrac{1+2+....+n}{2n^2}\)
4.\(lim\dfrac{3^n-4.2^{n-1}-10}{7.2^n+4^n}\)
Tính các giới hạn sau:
a) \(\lim\limits_{x\rightarrow0^-}\dfrac{2\left|x\right|+x}{x^2-x}\)
b) \(\lim\limits_{x\rightarrow-\infty}\left(\sqrt{x^2-x}-\sqrt{x^2-1}\right)\)
c) \(\lim\limits_{x\rightarrow-\infty}\dfrac{\sqrt[3]{1+x^4+x^6}}{\sqrt{1+x^3+x^4}}\)