早教吧作业答案频道 -->数学-->
lim(n^3)/(2*n^2+1)-(2*n^2)/(4n-1)n趋向于正无穷lim(n^3)/(2*n^2+1)-(2*n^2)/(4n-1)谢谢。。。。
题目详情
▼优质解答
答案和解析
lim(n→+∞) n^3/(2n^2+1)-2n^2/(4n-1)
=lim(n→+∞) [n^3(4n-1)-2n^2(2n^2+1)]/[(2n^2+1)(4n-1)
=lim(n→+∞) (-n^3-2n^2)/(12n^3-2n^2+4n-1)
=lim(n→+∞) (-1-2/n)/[12-2/n+4/n^2-1/n^3]
=-1/12
=lim(n→+∞) [n^3(4n-1)-2n^2(2n^2+1)]/[(2n^2+1)(4n-1)
=lim(n→+∞) (-n^3-2n^2)/(12n^3-2n^2+4n-1)
=lim(n→+∞) (-1-2/n)/[12-2/n+4/n^2-1/n^3]
=-1/12
看了lim(n^3)/(2*n^2...的网友还看了以下：