A) 7n+3/5n-12=7+3/n /5-12/n lim n→∞=7/5
b) (2+1/n-10/n²)/(n+12/n+20/n²) lim n→∞=0
c) lim n →∞ (6n-5)/(2n-3)+lim n →∞(4n-1)/(2n+3)=6/2+4/2=5
d) lim n →∞ (-n³+4n-10)/(5n²+n+21)=-∞
e) lim n →∞ (√n²+n-√n²+11)= lim n →∞ (n²+n-n²-11)/ (√n²+n+√n²+11)=
=lim n →∞ (n-11)/ (√n²+n+√n²+11)=lim n →∞ (1-11/n)/ (1+1/n+1+11/n²)=
= 1/2
g) lim n →∞ (1+1/3n)^n lim n →∞(1+k/n)^n=e^k k=1/3
lim n →∞ =e^1/3=∛e