Show that, without using L'Hospital's Rule:

Show that, without using L'Hospital's Rule:

Now you should encounter this indeterminate:

Instead of applying L'Hospital's Rule, read the hints again.
Now by expanding the hints, we shall notice that:
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No constant terms for xlnx, i.e. all terms are products of x. Then by putting x=0, we will yield the desired answer:
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Q.E.D.
Postscript: Mathjax is not so intuitive, so I use the below tool to create math pics:
Nice find. Since MathJax is a LaTeX-based renderer, you can actually skip the image-making step. If you copy the raw LaTeX string from that editor and paste it here, MathJax will render it as searchable, scalable text rather than a static image.
Great to know that.
I wonder when LibreOffice will support LaTeX someday.