Trả lời:

a) lim(√4n2+2n−2n)=lim4n2+2n−4n2√4n2+2n+2n=lim2n2n(√1+12n+1)
=lim1√1+12n+1=1√1+0+1=12.
a) lim(√4n2+2n−2n)=lim4n2+2n−4n2√4n2+2n+2n=lim2n2n(√1+12n+1)
=lim1√1+12n+1=1√1+0+1=12.