Let's take the limit y→∞lim(y2+1) Let's divide numerator and denominator by y^2: y→∞lim(y2+1) = y→∞lim(y211+y21) Do Replacement u=y1 then y→∞lim(y211+y21)=u→0+lim(u2u2+1) = 002+1=∞
The final answer: y→∞lim(y2+1)=∞
Lopital's rule
There is no sense to apply Lopital's rule to this function since there is no indeterminateness of 0/0 or oo/oo type