Recently I learned how to include just one page of a PDF file as image using \includegraphics, but now I need to include just part of the page and not the entire page.
How can I include just 50% or 65% of a PDF page as image in a document?
Recently I learned how to include just one page of a PDF file as image using \includegraphics, but now I need to include just part of the page and not the entire page.
How can I include just 50% or 65% of a PDF page as image in a document?
You can trim and clip an included image using the trim and clip key-values:

\documentclass{article}
\usepackage{graphicx}% http://ctan.org/pkg/graphicx
\begin{document}
\includegraphics[scale=.5]{example-image-a} \par
\includegraphics[trim=100 50 100 50,clip]{example-image-a}
\end{document}
The elements supplied to trim=<lx> <ly> <ux> <uy> are the bounding box values in bps.
Read up on the details in the Graphics Guide (section 4 The Graphics packages, p 7 onward).
adjustbox provides similar functionality.
Take a look at this question How can I crop included PDF documents?: Use pdfcrop from Heiko Oberdiek (requires Perl).
If you're using windows, you could just use the 'snipping tool' in programfiles/accessories to create an image of the portion of the pdf you want to put in as a picture.