For all Active Calculus texts, users should always view the HTML version of each as the definitive version: the HTML is easiest and fastest to update. You can always see the last date the HTML was updated by going to the book’s front matter page (for example, ACS).
For 2023, the vast majority of updates to Active Calculus Single Variable are minor; most of them are minor typos that shouldn’t cause any confusion between the PDF or print version (each of which are now several years old) and the HTML itself. There is primarily one section of the text where the changes are a bit more substantial: Section 3.1. In response to feedback from several different users, I’ve updated the First Derivative Text and a bit of the surrounding text. If you regularly work from the PDF or print version, I urge you to look at the HTML in advance when it’s time to consider that section with students.
Additionally, this year I’ve made public the alternate version of Chapter 8 at the landing page https://activecalculus.org/acs-8a/. Three key things about that version: (1) Chapter 8 is entirely different, taking a path through infinite series with the main emphasis being Taylor polynomials and Taylor series with limited emphasis on formal convergence issues; (2) Chapters 1-7 match completely with the original and standard version of the text, with the exception that all of the preview activities in the alternate version are rendered as interactive WeBWorK exercises, which in some cases means that a few of the questions are slightly different (primarily to make formerly open-ended questions more suited to WeBWorK feedback); and (3) the alternate version is only available in HTML at this time. One of the reasons for (2) is that the alternate version of the text is the one that we’ve chosen for the Runestone version that’s available this fall and discussed in this earlier post.
Finally, for Active Prelude: like for the standard version of Active Single, the HTML has been recently updated, and nearly all of the changes are to correct minor typos. There shouldn’t be anything confusing between the print or PDF versions and what’s present in the HTML, though again the HTML will have the fewest errors.
There is certainly more work ahead and in the coming year I hope to make considerable progress on other issues that have been raised. As my favorite example so far, a couple of users have pointed out a fact I didn’t realize: the long-term temperature of a potato in an oven approaches 212 degrees Fahrenheit, not the temperature of the oven itself. This fact means that several activities and discussions need to be updated, and that will occur in the next official version of the text; I chose not to make those changes this year since it would lead to differences in the Activities Workbooks and I feared this would mean greater potential for short-term confusion.
As ever, I am immensely grateful to users who submit errors and suggestions. Please keep sending them to me, ideally via email at boelkinm at gvsu dot edu.