i.e. limit for the numerator is x→∞limx=∞ and limit for the denominator is x→∞lim9x2+1=∞ Let's take derivatives of the numerator and denominator until we eliminate indeterninateness. x→∞lim(9x2+1x) = x→∞lim(dxd9x2+1dxdx) = x→∞lim(9x9x2+1) = x→∞lim(9x9x2+1) = 31 It can be seen that we have applied Lopital's rule (we have taken derivatives with respect to the numerator and denominator) 1 time(s)