$$\lim_{x \to \infty}\left(\left(\left(- \operatorname{atan}{\left(2 x \right)} - \operatorname{atan}{\left(5 x \right)}\right) + 2 \operatorname{atan}{\left(x \right)}\right) - \frac{\pi}{2}\right) = - \frac{\pi}{2}$$
$$\lim_{x \to 0^-}\left(\left(\left(- \operatorname{atan}{\left(2 x \right)} - \operatorname{atan}{\left(5 x \right)}\right) + 2 \operatorname{atan}{\left(x \right)}\right) - \frac{\pi}{2}\right) = - \frac{\pi}{2}$$
Más detalles con x→0 a la izquierda$$\lim_{x \to 0^+}\left(\left(\left(- \operatorname{atan}{\left(2 x \right)} - \operatorname{atan}{\left(5 x \right)}\right) + 2 \operatorname{atan}{\left(x \right)}\right) - \frac{\pi}{2}\right) = - \frac{\pi}{2}$$
Más detalles con x→0 a la derecha$$\lim_{x \to 1^-}\left(\left(\left(- \operatorname{atan}{\left(2 x \right)} - \operatorname{atan}{\left(5 x \right)}\right) + 2 \operatorname{atan}{\left(x \right)}\right) - \frac{\pi}{2}\right) = - \operatorname{atan}{\left(5 \right)} - \operatorname{atan}{\left(2 \right)}$$
Más detalles con x→1 a la izquierda$$\lim_{x \to 1^+}\left(\left(\left(- \operatorname{atan}{\left(2 x \right)} - \operatorname{atan}{\left(5 x \right)}\right) + 2 \operatorname{atan}{\left(x \right)}\right) - \frac{\pi}{2}\right) = - \operatorname{atan}{\left(5 \right)} - \operatorname{atan}{\left(2 \right)}$$
Más detalles con x→1 a la derecha$$\lim_{x \to -\infty}\left(\left(\left(- \operatorname{atan}{\left(2 x \right)} - \operatorname{atan}{\left(5 x \right)}\right) + 2 \operatorname{atan}{\left(x \right)}\right) - \frac{\pi}{2}\right) = - \frac{\pi}{2}$$
Más detalles con x→-oo