求极限 3n^2-4n+4/2-n^2

求极限 3n^2-4n+4/2-n^2
求极限 3n^2-4n+4/2-n^2

求极限 3n^2-4n+4/2-n^2
(3n^2-4n+4)/(2-n^2)
=(3n^2-6-4n+10)/(2-n^2)
=-3+(10-4n)/(2-n^2)
=-3-(4/n+10/n^2)/(-1+2/n^2)
n趋向于无穷大,-4/n+10/n^2趋向于0,2/n^2-1趋向于-1
lim(3n^2-4n+4)/(2-n^2)=-3