\(\lim\left(\dfrac{\sqrt[3]{an^3+n}}{n+2}-1\right)=\lim\left(\dfrac{\sqrt[3]{a+\dfrac{1}{n^2}}}{1+\dfrac{2}{n}}-1\right)=\sqrt[3]{a}-1\)
\(\Rightarrow\sqrt[3]{a}-1=2\Rightarrow a=27\)
\(\lim\left(\dfrac{\sqrt[3]{an^3+n}}{n+2}-1\right)=\lim\left(\dfrac{\sqrt[3]{a+\dfrac{1}{n^2}}}{1+\dfrac{2}{n}}-1\right)=\sqrt[3]{a}-1\)
\(\Rightarrow\sqrt[3]{a}-1=2\Rightarrow a=27\)
tìm giới hạn của dãy số
1.\(\lim\limits_{n->\infty}\left(\sqrt[3]{n^3+n^2+n+1}-n\right)\)
2.\(\lim\limits_{n->\infty}\left(\sqrt{n^2+n}-\sqrt{n^2-n+1}\right)\)
3.tìm a,b để \(\lim\limits_{n->\infty}\left(\sqrt{an^2+bn+2}-2n\right)=2\)
đặt \(a=lim\dfrac{\sqrt{2n+1}}{\sqrt{n}+1}\). tìm giới hạn \(lim\dfrac{3-4an^2}{\left(an-2\right)^2}\)
biết \(lim\dfrac{\sqrt{\left(3-4n\right)^2+1}+an-1}{\sqrt{n^2+4n+1}+an}=2\). tìm a
Tìm các giới hạn sau:
a)\(lim\left[n^2\left(\sqrt{n^2+2}-\sqrt{n^2+4}\right)\right]\)
b)lim( \(\dfrac{3}{n-2}-5n\))
c) lim(\(\dfrac{n-1}{\sqrt{3}-n}-\dfrac{4}{2^{-n}}\))
d) \(lim\left(\dfrac{n^2-4}{n-2}-\dfrac{3n^2+4}{n}\right)\)
e) \(lim\dfrac{\sqrt{n^2+1}-n\sqrt{5}}{\sqrt{n^2+1}+n\sqrt{5}}\)
Tìm các giới hạn sau:
a) \(lim\sqrt[3]{-n^3+2n^2-5}\)
b) \(lim\dfrac{1}{\sqrt{n+1}-\sqrt{n}}\)
c) \(lim\left(\dfrac{1}{n+1}-n\right)\)
d) \(lim\left(\dfrac{2n^2-1}{n+1}-2n\right)\)
e) \(lim\dfrac{2n^3+n^2-3n+1}{2-3n}\)
Tính các giới hạn sau
1,Lim\(\left(\dfrac{2n^3}{2n^2+3}+\dfrac{1-5n^2}{5n+1}\right)\)
2,a,Lim\(\left(\sqrt{n^2+n}-\sqrt{n^2+2}\right)\)
b,Lim\(\dfrac{\sqrt{n^4+3n-2}}{2n^2-n+3}\)
c,Lim\(\dfrac{\sqrt{n^2-4n}-\sqrt{4n^2+1}}{\sqrt{3n^2+1}-n}\)
Tìm các giới hạn sau:
\(a,lim\dfrac{\sqrt{n^2+n-1}-n}{2n+3}\)
\(b,lim\left(\sqrt[3]{n^3+1}+\sqrt{n^2+n}-2n\right)\)
Tìm các giới hạn sau:
\(a,lim\dfrac{\sqrt{n^2+n-1}-n}{2n+3}\)
\(b,lim\left(\sqrt[3]{n^3+1}+\sqrt{n^2+n}-2n\right)\)
Tìm các giới hạn sau:
\(a,lim\dfrac{\sqrt[3]{8n^3+2n}}{-n+3}\)
\(b,lim\dfrac{\left(2n\sqrt{n}+1\right)\left(\sqrt{n}+3\right)}{\left(n-1\right)\left(3-2n\right)}\)