Sometimes in editing pages on the Library, a page will be edited and it may look something like the page shown below for the first chapter's exercise set in the OpenStax Calculus text.
This is a transcluded page like the procedure outlined in Section 2.8. To edit the content on this page (to fix a typo or incorrect image, etc.), the source page must be located and edited directly. If you are not the textbook's author, remember to only fix errors on the original source pages and only customize pages that are located in your school's Course Shell.
To quickly navigate to the corresponding source page to edit it, double click on the purple "Content Reuse" box and a Content Reuse window will pop up.
Copy and paste the URL in the "Article to reuse" which is the source page. Then paste it in the URL wtih the after appending it to the name of the library (Math library in this case).
When the new page (source) opens up, you can edit it as with other pages. Any edits on this source page will be reflected on the transcluded page as well, once it is refreshed.