Question

Tìm các giới hạn sau:

\(a,lim\dfrac{7n^2-3n}{n^2+2}\)

\(b,lim\dfrac{2n^2+1}{3n^3-3n+3}\)

Answer 1

\(b,lim\dfrac{2n^2+1}{3n^3-3n+3}\)

\(=lim\dfrac{2n+\dfrac{1}{n^3}}{3-\dfrac{3}{n^2}+\dfrac{3}{n^3}}\)

\(=n\times\dfrac{2}{3}=\)+∞

Answer 2

A, 7.b dương vô cực

Answer 3

\(a,lim\dfrac{7n^2-3n}{n^2+2}\)

\(=lim\dfrac{7-\dfrac{3}{n}}{1+\dfrac{2}{n^2}}\)

\(=\dfrac{7-0}{1+0}=\dfrac{7}{1}=7\)

Answer 4

\(\lim\dfrac{2n^2+1}{3n^3-3n+3}=\lim\dfrac{2+\dfrac{1}{n^2}}{3n-\dfrac{3}{n}+\dfrac{3}{n^3}}=\dfrac{2}{+\infty}=0\)