$$\lim_{x \to \infty}\left(x - \operatorname{atan}{\left(5 x \right)}\right) = \infty$$
$$\lim_{x \to 0^-}\left(x - \operatorname{atan}{\left(5 x \right)}\right) = 0$$
More at x→0 from the left$$\lim_{x \to 0^+}\left(x - \operatorname{atan}{\left(5 x \right)}\right) = 0$$
More at x→0 from the right$$\lim_{x \to 1^-}\left(x - \operatorname{atan}{\left(5 x \right)}\right) = 1 - \operatorname{atan}{\left(5 \right)}$$
More at x→1 from the left$$\lim_{x \to 1^+}\left(x - \operatorname{atan}{\left(5 x \right)}\right) = 1 - \operatorname{atan}{\left(5 \right)}$$
More at x→1 from the right$$\lim_{x \to -\infty}\left(x - \operatorname{atan}{\left(5 x \right)}\right) = -\infty$$
More at x→-oo