While writing down the above expression on Overleaf, I encountered the problem of drawing the dashed line in between the Left Hand Side and the Right Hand Side expressions. Do help me in writing it exactly that way.
(I had written it in my own unique way, but without the dashed line, and would be intrigued to know if such a function existed.)
My code & Output:
\documentclass{article}
\usepackage{amsmath}
\begin{document}
ARCTAN TERMS:
\[\boxed{\sqrt{2}\zeta_1+1 \to \infty \implies \tan^{-1}(\sqrt{2}\zeta_1+1)\rightarrow \dfrac{\pi}{2}}\text{ and } \boxed{\sqrt{2}\zeta_1+1 \rightarrow -\infty \implies \tan^{-1}(\sqrt{2}\zeta_1+1)\to \dfrac{-\pi}{2}}\]
\[\boxed{\sqrt{2}\zeta_1-1 \to \infty \implies \tan^{-1}(\sqrt{2}\zeta_1-1)\rightarrow \dfrac{\pi}{2}}\text{ and } \boxed{\sqrt{2}\zeta_1-1 \rightarrow -\infty \implies \tan^{-1}(\sqrt{2}\zeta_1-1)\to \dfrac{-\pi}{2}}\]
Hence, \[\text{ Arctan terms evaluates to } \frac{\sqrt{2}}{4}\left(\frac{\pi}{2}+\frac{\pi}{2}-\left(\frac{-\pi}{2}-\frac{\pi}{2}\right)\right)=\frac{\pi}{\sqrt2}\]
\end{document}
Output:





\documentclass{...}, the required\usepackage's,\begin{document}, and\end{document}. That may seem tedious to you, but think of the extra work it represents for the users willing to give you a hand. Help them help you: remove that one hurdle between you and a solution to your problem.\[ … \]preferable to$$?\usepackage{amsmath}will generate errors in the place you show it, so you will need to move that.