How about using the home page calculator?
$${\mathtt{36}}{\mathtt{\,-\,}}{\frac{{{\mathtt{e}}}^{{\mathtt{x2}}}}{{\mathtt{1}}}}{\mathtt{\,-\,}}{{\mathtt{e}}}^{{\mathtt{36}}}{\mathtt{\,-\,}}{\mathtt{x2}} = {\mathtt{\,-\,}}{\mathtt{x2}}{\mathtt{\,-\,}}\left({{\mathtt{e}}}^{{\mathtt{x2}}}\right){\mathtt{\,-\,}}\left({{\mathtt{e}}}^{{\mathtt{36}}}\right){\mathtt{\,\small\textbf+\,}}{\mathtt{36}}$$
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