As part of this problem, after substitution I need to calculate the new limits.
However, I do not understand why this is so:
$\lim_{x \to \infty}\space{\arctan(x)} = \frac{\pi}{2}$
I tried drawing the unit circle to see what happens with $\arctan$ when $x \to \infty$ but I don't know how to draw $\arctan$. It is the inverse of $\tan$ but do you even draw $\tan$?
I would appreciate any help.