We have indeterminateness of type
oo/oo,
i.e. limit for the numerator is
$$\lim_{n \to \infty}\left(\frac{\left(n + 2\right)^{2}}{n}\right) = \infty$$
and limit for the denominator is
$$\lim_{n \to \infty}\left(n + 3\right) = \infty$$
Let's take derivatives of the numerator and denominator until we eliminate indeterninateness.
$$\lim_{n \to \infty}\left(\frac{\left(n + 2\right)^{2}}{n \left(n + 3\right)}\right)$$
=
Let's transform the function under the limit a few
$$\lim_{n \to \infty}\left(\frac{\left(n + 2\right)^{2}}{n \left(n + 3\right)}\right)$$
=
$$\lim_{n \to \infty}\left(\frac{\frac{d}{d n} \frac{\left(n + 2\right)^{2}}{n}}{\frac{d}{d n} \left(n + 3\right)}\right)$$
=
$$\lim_{n \to \infty}\left(1 - \frac{4}{n^{2}}\right)$$
=
$$\lim_{n \to \infty}\left(1 - \frac{4}{n^{2}}\right)$$
=
$$1$$
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)