You can print a PDF document using the iBooksapp on your iPhone X. Here's how to do it:

1. On your iPhone X, open iBooks.
2. At the top of the screen, tap the menu.
3. If a pop-up menu appears, choose PDFs from the list of possibilities.
4. Select the PDF document you wish to print or email by tapping it.
5. At the top of the navigation bar, tap the Share icon. If the menu isn't visible, tap anywhere on the screen once to bring it up.
6. Select Print or Email from the drop-down menu.
7. If you wish to print the PDF document, choose Print; alternatively, choose Email to send it to someone through email.
8. To print a PDF on your iPhone X, select an AirPrint printer, specify a page range, and number or copies and then tap Print.

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