Detail solution
Let's take the limit
$$\lim_{x \to \infty} \left(\frac{x + 1}{x + 2}\right)^{x + 1}$$
transform
$$\lim_{x \to \infty} \left(\frac{x + 1}{x + 2}\right)^{x + 1}$$
=
$$\lim_{x \to \infty} \left(\frac{\left(x + 2\right) - 1}{x + 2}\right)^{x + 1}$$
=
$$\lim_{x \to \infty} \left(- \frac{1}{x + 2} + \frac{x + 2}{x + 2}\right)^{x + 1}$$
=
$$\lim_{x \to \infty} \left(1 - \frac{1}{x + 2}\right)^{x + 1}$$
=
do replacement
$$u = \frac{x + 2}{-1}$$
then
$$\lim_{x \to \infty} \left(1 - \frac{1}{x + 2}\right)^{x + 1}$$ =
=
$$\lim_{u \to \infty} \left(1 + \frac{1}{u}\right)^{- u - 1}$$
=
$$\lim_{u \to \infty}\left(\frac{\left(1 + \frac{1}{u}\right)^{- u}}{1 + \frac{1}{u}}\right)$$
=
$$\lim_{u \to \infty} \frac{1}{1 + \frac{1}{u}} \lim_{u \to \infty} \left(1 + \frac{1}{u}\right)^{- u}$$
=
$$\lim_{u \to \infty} \left(1 + \frac{1}{u}\right)^{- u}$$
=
$$\left(\left(\lim_{u \to \infty} \left(1 + \frac{1}{u}\right)^{u}\right)\right)^{-1}$$
The limit
$$\lim_{u \to \infty} \left(1 + \frac{1}{u}\right)^{u}$$
is second remarkable limit, is equal to e ~ 2.718281828459045
then
$$\left(\left(\lim_{u \to \infty} \left(1 + \frac{1}{u}\right)^{u}\right)\right)^{-1} = e^{-1}$$
The final answer:
$$\lim_{x \to \infty} \left(\frac{x + 1}{x + 2}\right)^{x + 1} = e^{-1}$$